net_processing.cpp
1 // Copyright (c) 2009-2010 Satoshi Nakamoto 2 // Copyright (c) 2009-present The Bitcoin Core developers 3 // Distributed under the MIT software license, see the accompanying 4 // file COPYING or http://www.opensource.org/licenses/mit-license.php. 5 6 #include <net_processing.h> 7 8 #include <addrman.h> 9 #include <arith_uint256.h> 10 #include <banman.h> 11 #include <blockencodings.h> 12 #include <blockfilter.h> 13 #include <chain.h> 14 #include <chainparams.h> 15 #include <common/bloom.h> 16 #include <consensus/amount.h> 17 #include <consensus/params.h> 18 #include <consensus/validation.h> 19 #include <core_memusage.h> 20 #include <crypto/siphash.h> 21 #include <deploymentstatus.h> 22 #include <flatfile.h> 23 #include <headerssync.h> 24 #include <index/blockfilterindex.h> 25 #include <kernel/chain.h> 26 #include <logging.h> 27 #include <merkleblock.h> 28 #include <net.h> 29 #include <net_permissions.h> 30 #include <netaddress.h> 31 #include <netbase.h> 32 #include <netmessagemaker.h> 33 #include <node/blockstorage.h> 34 #include <node/connection_types.h> 35 #include <node/protocol_version.h> 36 #include <node/timeoffsets.h> 37 #include <node/txdownloadman.h> 38 #include <node/txreconciliation.h> 39 #include <node/warnings.h> 40 #include <policy/feerate.h> 41 #include <policy/fees.h> 42 #include <policy/packages.h> 43 #include <policy/policy.h> 44 #include <primitives/block.h> 45 #include <primitives/transaction.h> 46 #include <protocol.h> 47 #include <random.h> 48 #include <scheduler.h> 49 #include <script/script.h> 50 #include <serialize.h> 51 #include <span.h> 52 #include <streams.h> 53 #include <sync.h> 54 #include <tinyformat.h> 55 #include <txmempool.h> 56 #include <txorphanage.h> 57 #include <uint256.h> 58 #include <util/check.h> 59 #include <util/strencodings.h> 60 #include <util/time.h> 61 #include <util/trace.h> 62 #include <validation.h> 63 64 #include <algorithm> 65 #include <array> 66 #include <atomic> 67 #include <compare> 68 #include <cstddef> 69 #include <deque> 70 #include <exception> 71 #include <functional> 72 #include <future> 73 #include <initializer_list> 74 #include <iterator> 75 #include <limits> 76 #include <list> 77 #include <map> 78 #include <memory> 79 #include <optional> 80 #include <queue> 81 #include <ranges> 82 #include <ratio> 83 #include <set> 84 #include <span> 85 #include <typeinfo> 86 #include <utility> 87 88 using namespace util::hex_literals; 89 90 TRACEPOINT_SEMAPHORE(net, inbound_message); 91 TRACEPOINT_SEMAPHORE(net, misbehaving_connection); 92 93 /** Headers download timeout. 94 * Timeout = base + per_header * (expected number of headers) */ 95 static constexpr auto HEADERS_DOWNLOAD_TIMEOUT_BASE = 15min; 96 static constexpr auto HEADERS_DOWNLOAD_TIMEOUT_PER_HEADER = 1ms; 97 /** How long to wait for a peer to respond to a getheaders request */ 98 static constexpr auto HEADERS_RESPONSE_TIME{2min}; 99 /** Protect at least this many outbound peers from disconnection due to slow/ 100 * behind headers chain. 101 */ 102 static constexpr int32_t MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT = 4; 103 /** Timeout for (unprotected) outbound peers to sync to our chainwork */ 104 static constexpr auto CHAIN_SYNC_TIMEOUT{20min}; 105 /** How frequently to check for stale tips */ 106 static constexpr auto STALE_CHECK_INTERVAL{10min}; 107 /** How frequently to check for extra outbound peers and disconnect */ 108 static constexpr auto EXTRA_PEER_CHECK_INTERVAL{45s}; 109 /** Minimum time an outbound-peer-eviction candidate must be connected for, in order to evict */ 110 static constexpr auto MINIMUM_CONNECT_TIME{30s}; 111 /** SHA256("main address relay")[0:8] */ 112 static constexpr uint64_t RANDOMIZER_ID_ADDRESS_RELAY = 0x3cac0035b5866b90ULL; 113 /// Age after which a stale block will no longer be served if requested as 114 /// protection against fingerprinting. Set to one month, denominated in seconds. 115 static constexpr int STALE_RELAY_AGE_LIMIT = 30 * 24 * 60 * 60; 116 /// Age after which a block is considered historical for purposes of rate 117 /// limiting block relay. Set to one week, denominated in seconds. 118 static constexpr int HISTORICAL_BLOCK_AGE = 7 * 24 * 60 * 60; 119 /** Time between pings automatically sent out for latency probing and keepalive */ 120 static constexpr auto PING_INTERVAL{2min}; 121 /** The maximum number of entries in a locator */ 122 static const unsigned int MAX_LOCATOR_SZ = 101; 123 /** The maximum number of entries in an 'inv' protocol message */ 124 static const unsigned int MAX_INV_SZ = 50000; 125 /** Limit to avoid sending big packets. Not used in processing incoming GETDATA for compatibility */ 126 static const unsigned int MAX_GETDATA_SZ = 1000; 127 /** Number of blocks that can be requested at any given time from a single peer. */ 128 static const int MAX_BLOCKS_IN_TRANSIT_PER_PEER = 16; 129 /** Default time during which a peer must stall block download progress before being disconnected. 130 * the actual timeout is increased temporarily if peers are disconnected for hitting the timeout */ 131 static constexpr auto BLOCK_STALLING_TIMEOUT_DEFAULT{2s}; 132 /** Maximum timeout for stalling block download. */ 133 static constexpr auto BLOCK_STALLING_TIMEOUT_MAX{64s}; 134 /** Maximum depth of blocks we're willing to serve as compact blocks to peers 135 * when requested. For older blocks, a regular BLOCK response will be sent. */ 136 static const int MAX_CMPCTBLOCK_DEPTH = 5; 137 /** Maximum depth of blocks we're willing to respond to GETBLOCKTXN requests for. */ 138 static const int MAX_BLOCKTXN_DEPTH = 10; 139 static_assert(MAX_BLOCKTXN_DEPTH <= MIN_BLOCKS_TO_KEEP, "MAX_BLOCKTXN_DEPTH too high"); 140 /** Size of the "block download window": how far ahead of our current height do we fetch? 141 * Larger windows tolerate larger download speed differences between peer, but increase the potential 142 * degree of disordering of blocks on disk (which make reindexing and pruning harder). We'll probably 143 * want to make this a per-peer adaptive value at some point. */ 144 static const unsigned int BLOCK_DOWNLOAD_WINDOW = 1024; 145 /** Block download timeout base, expressed in multiples of the block interval (i.e. 10 min) */ 146 static constexpr double BLOCK_DOWNLOAD_TIMEOUT_BASE = 1; 147 /** Additional block download timeout per parallel downloading peer (i.e. 5 min) */ 148 static constexpr double BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 0.5; 149 /** Maximum number of headers to announce when relaying blocks with headers message.*/ 150 static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8; 151 /** Minimum blocks required to signal NODE_NETWORK_LIMITED */ 152 static const unsigned int NODE_NETWORK_LIMITED_MIN_BLOCKS = 288; 153 /** Window, in blocks, for connecting to NODE_NETWORK_LIMITED peers */ 154 static const unsigned int NODE_NETWORK_LIMITED_ALLOW_CONN_BLOCKS = 144; 155 /** Average delay between local address broadcasts */ 156 static constexpr auto AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL{24h}; 157 /** Average delay between peer address broadcasts */ 158 static constexpr auto AVG_ADDRESS_BROADCAST_INTERVAL{30s}; 159 /** Delay between rotating the peers we relay a particular address to */ 160 static constexpr auto ROTATE_ADDR_RELAY_DEST_INTERVAL{24h}; 161 /** Average delay between trickled inventory transmissions for inbound peers. 162 * Blocks and peers with NetPermissionFlags::NoBan permission bypass this. */ 163 static constexpr auto INBOUND_INVENTORY_BROADCAST_INTERVAL{5s}; 164 /** Average delay between trickled inventory transmissions for outbound peers. 165 * Use a smaller delay as there is less privacy concern for them. 166 * Blocks and peers with NetPermissionFlags::NoBan permission bypass this. */ 167 static constexpr auto OUTBOUND_INVENTORY_BROADCAST_INTERVAL{2s}; 168 /** Maximum rate of inventory items to send per second. 169 * Limits the impact of low-fee transaction floods. */ 170 static constexpr unsigned int INVENTORY_BROADCAST_PER_SECOND = 7; 171 /** Target number of tx inventory items to send per transmission. */ 172 static constexpr unsigned int INVENTORY_BROADCAST_TARGET = INVENTORY_BROADCAST_PER_SECOND * count_seconds(INBOUND_INVENTORY_BROADCAST_INTERVAL); 173 /** Maximum number of inventory items to send per transmission. */ 174 static constexpr unsigned int INVENTORY_BROADCAST_MAX = 1000; 175 static_assert(INVENTORY_BROADCAST_MAX >= INVENTORY_BROADCAST_TARGET, "INVENTORY_BROADCAST_MAX too low"); 176 static_assert(INVENTORY_BROADCAST_MAX <= node::MAX_PEER_TX_ANNOUNCEMENTS, "INVENTORY_BROADCAST_MAX too high"); 177 /** Average delay between feefilter broadcasts in seconds. */ 178 static constexpr auto AVG_FEEFILTER_BROADCAST_INTERVAL{10min}; 179 /** Maximum feefilter broadcast delay after significant change. */ 180 static constexpr auto MAX_FEEFILTER_CHANGE_DELAY{5min}; 181 /** Maximum number of compact filters that may be requested with one getcfilters. See BIP 157. */ 182 static constexpr uint32_t MAX_GETCFILTERS_SIZE = 1000; 183 /** Maximum number of cf hashes that may be requested with one getcfheaders. See BIP 157. */ 184 static constexpr uint32_t MAX_GETCFHEADERS_SIZE = 2000; 185 /** the maximum percentage of addresses from our addrman to return in response to a getaddr message. */ 186 static constexpr size_t MAX_PCT_ADDR_TO_SEND = 23; 187 /** The maximum number of address records permitted in an ADDR message. */ 188 static constexpr size_t MAX_ADDR_TO_SEND{1000}; 189 /** The maximum rate of address records we're willing to process on average. Can be bypassed using 190 * the NetPermissionFlags::Addr permission. */ 191 static constexpr double MAX_ADDR_RATE_PER_SECOND{0.1}; 192 /** The soft limit of the address processing token bucket (the regular MAX_ADDR_RATE_PER_SECOND 193 * based increments won't go above this, but the MAX_ADDR_TO_SEND increment following GETADDR 194 * is exempt from this limit). */ 195 static constexpr size_t MAX_ADDR_PROCESSING_TOKEN_BUCKET{MAX_ADDR_TO_SEND}; 196 /** The compactblocks version we support. See BIP 152. */ 197 static constexpr uint64_t CMPCTBLOCKS_VERSION{2}; 198 199 // Internal stuff 200 namespace { 201 /** Blocks that are in flight, and that are in the queue to be downloaded. */ 202 struct QueuedBlock { 203 /** BlockIndex. We must have this since we only request blocks when we've already validated the header. */ 204 const CBlockIndex* pindex; 205 /** Optional, used for CMPCTBLOCK downloads */ 206 std::unique_ptr<PartiallyDownloadedBlock> partialBlock; 207 }; 208 209 /** 210 * Data structure for an individual peer. This struct is not protected by 211 * cs_main since it does not contain validation-critical data. 212 * 213 * Memory is owned by shared pointers and this object is destructed when 214 * the refcount drops to zero. 215 * 216 * Mutexes inside this struct must not be held when locking m_peer_mutex. 217 * 218 * TODO: move most members from CNodeState to this structure. 219 * TODO: move remaining application-layer data members from CNode to this structure. 220 */ 221 struct Peer { 222 /** Same id as the CNode object for this peer */ 223 const NodeId m_id{0}; 224 225 /** Services we offered to this peer. 226 * 227 * This is supplied by CConnman during peer initialization. It's const 228 * because there is no protocol defined for renegotiating services 229 * initially offered to a peer. The set of local services we offer should 230 * not change after initialization. 231 * 232 * An interesting example of this is NODE_NETWORK and initial block 233 * download: a node which starts up from scratch doesn't have any blocks 234 * to serve, but still advertises NODE_NETWORK because it will eventually 235 * fulfill this role after IBD completes. P2P code is written in such a 236 * way that it can gracefully handle peers who don't make good on their 237 * service advertisements. */ 238 const ServiceFlags m_our_services; 239 /** Services this peer offered to us. */ 240 std::atomic<ServiceFlags> m_their_services{NODE_NONE}; 241 242 //! Whether this peer is an inbound connection 243 const bool m_is_inbound; 244 245 /** Protects misbehavior data members */ 246 Mutex m_misbehavior_mutex; 247 /** Whether this peer should be disconnected and marked as discouraged (unless it has NetPermissionFlags::NoBan permission). */ 248 bool m_should_discourage GUARDED_BY(m_misbehavior_mutex){false}; 249 250 /** Protects block inventory data members */ 251 Mutex m_block_inv_mutex; 252 /** List of blocks that we'll announce via an `inv` message. 253 * There is no final sorting before sending, as they are always sent 254 * immediately and in the order requested. */ 255 std::vector<uint256> m_blocks_for_inv_relay GUARDED_BY(m_block_inv_mutex); 256 /** Unfiltered list of blocks that we'd like to announce via a `headers` 257 * message. If we can't announce via a `headers` message, we'll fall back to 258 * announcing via `inv`. */ 259 std::vector<uint256> m_blocks_for_headers_relay GUARDED_BY(m_block_inv_mutex); 260 /** The final block hash that we sent in an `inv` message to this peer. 261 * When the peer requests this block, we send an `inv` message to trigger 262 * the peer to request the next sequence of block hashes. 263 * Most peers use headers-first syncing, which doesn't use this mechanism */ 264 uint256 m_continuation_block GUARDED_BY(m_block_inv_mutex) {}; 265 266 /** Set to true once initial VERSION message was sent (only relevant for outbound peers). */ 267 bool m_outbound_version_message_sent GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false}; 268 269 /** This peer's reported block height when we connected */ 270 std::atomic<int> m_starting_height{-1}; 271 272 /** The pong reply we're expecting, or 0 if no pong expected. */ 273 std::atomic<uint64_t> m_ping_nonce_sent{0}; 274 /** When the last ping was sent, or 0 if no ping was ever sent */ 275 std::atomic<std::chrono::microseconds> m_ping_start{0us}; 276 /** Whether a ping has been requested by the user */ 277 std::atomic<bool> m_ping_queued{false}; 278 279 /** Whether this peer relays txs via wtxid */ 280 std::atomic<bool> m_wtxid_relay{false}; 281 /** The feerate in the most recent BIP133 `feefilter` message sent to the peer. 282 * It is *not* a p2p protocol violation for the peer to send us 283 * transactions with a lower fee rate than this. See BIP133. */ 284 CAmount m_fee_filter_sent GUARDED_BY(NetEventsInterface::g_msgproc_mutex){0}; 285 /** Timestamp after which we will send the next BIP133 `feefilter` message 286 * to the peer. */ 287 std::chrono::microseconds m_next_send_feefilter GUARDED_BY(NetEventsInterface::g_msgproc_mutex){0}; 288 289 struct TxRelay { 290 mutable RecursiveMutex m_bloom_filter_mutex; 291 /** Whether we relay transactions to this peer. */ 292 bool m_relay_txs GUARDED_BY(m_bloom_filter_mutex){false}; 293 /** A bloom filter for which transactions to announce to the peer. See BIP37. */ 294 std::unique_ptr<CBloomFilter> m_bloom_filter PT_GUARDED_BY(m_bloom_filter_mutex) GUARDED_BY(m_bloom_filter_mutex){nullptr}; 295 296 mutable RecursiveMutex m_tx_inventory_mutex; 297 /** A filter of all the (w)txids that the peer has announced to 298 * us or we have announced to the peer. We use this to avoid announcing 299 * the same (w)txid to a peer that already has the transaction. */ 300 CRollingBloomFilter m_tx_inventory_known_filter GUARDED_BY(m_tx_inventory_mutex){50000, 0.000001}; 301 /** Set of transaction ids we still have to announce (txid for 302 * non-wtxid-relay peers, wtxid for wtxid-relay peers). We use the 303 * mempool to sort transactions in dependency order before relay, so 304 * this does not have to be sorted. */ 305 std::set<uint256> m_tx_inventory_to_send GUARDED_BY(m_tx_inventory_mutex); 306 /** Whether the peer has requested us to send our complete mempool. Only 307 * permitted if the peer has NetPermissionFlags::Mempool or we advertise 308 * NODE_BLOOM. See BIP35. */ 309 bool m_send_mempool GUARDED_BY(m_tx_inventory_mutex){false}; 310 /** The next time after which we will send an `inv` message containing 311 * transaction announcements to this peer. */ 312 std::chrono::microseconds m_next_inv_send_time GUARDED_BY(m_tx_inventory_mutex){0}; 313 /** The mempool sequence num at which we sent the last `inv` message to this peer. 314 * Can relay txs with lower sequence numbers than this (see CTxMempool::info_for_relay). */ 315 uint64_t m_last_inv_sequence GUARDED_BY(NetEventsInterface::g_msgproc_mutex){1}; 316 317 /** Minimum fee rate with which to filter transaction announcements to this node. See BIP133. */ 318 std::atomic<CAmount> m_fee_filter_received{0}; 319 }; 320 321 /* Initializes a TxRelay struct for this peer. Can be called at most once for a peer. */ 322 TxRelay* SetTxRelay() EXCLUSIVE_LOCKS_REQUIRED(!m_tx_relay_mutex) 323 { 324 LOCK(m_tx_relay_mutex); 325 Assume(!m_tx_relay); 326 m_tx_relay = std::make_unique<Peer::TxRelay>(); 327 return m_tx_relay.get(); 328 }; 329 330 TxRelay* GetTxRelay() EXCLUSIVE_LOCKS_REQUIRED(!m_tx_relay_mutex) 331 { 332 return WITH_LOCK(m_tx_relay_mutex, return m_tx_relay.get()); 333 }; 334 335 /** A vector of addresses to send to the peer, limited to MAX_ADDR_TO_SEND. */ 336 std::vector<CAddress> m_addrs_to_send GUARDED_BY(NetEventsInterface::g_msgproc_mutex); 337 /** Probabilistic filter to track recent addr messages relayed with this 338 * peer. Used to avoid relaying redundant addresses to this peer. 339 * 340 * We initialize this filter for outbound peers (other than 341 * block-relay-only connections) or when an inbound peer sends us an 342 * address related message (ADDR, ADDRV2, GETADDR). 343 * 344 * Presence of this filter must correlate with m_addr_relay_enabled. 345 **/ 346 std::unique_ptr<CRollingBloomFilter> m_addr_known GUARDED_BY(NetEventsInterface::g_msgproc_mutex); 347 /** Whether we are participating in address relay with this connection. 348 * 349 * We set this bool to true for outbound peers (other than 350 * block-relay-only connections), or when an inbound peer sends us an 351 * address related message (ADDR, ADDRV2, GETADDR). 352 * 353 * We use this bool to decide whether a peer is eligible for gossiping 354 * addr messages. This avoids relaying to peers that are unlikely to 355 * forward them, effectively blackholing self announcements. Reasons 356 * peers might support addr relay on the link include that they connected 357 * to us as a block-relay-only peer or they are a light client. 358 * 359 * This field must correlate with whether m_addr_known has been 360 * initialized.*/ 361 std::atomic_bool m_addr_relay_enabled{false}; 362 /** Whether a getaddr request to this peer is outstanding. */ 363 bool m_getaddr_sent GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false}; 364 /** Guards address sending timers. */ 365 mutable Mutex m_addr_send_times_mutex; 366 /** Time point to send the next ADDR message to this peer. */ 367 std::chrono::microseconds m_next_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; 368 /** Time point to possibly re-announce our local address to this peer. */ 369 std::chrono::microseconds m_next_local_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; 370 /** Whether the peer has signaled support for receiving ADDRv2 (BIP155) 371 * messages, indicating a preference to receive ADDRv2 instead of ADDR ones. */ 372 std::atomic_bool m_wants_addrv2{false}; 373 /** Whether this peer has already sent us a getaddr message. */ 374 bool m_getaddr_recvd GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false}; 375 /** Number of addresses that can be processed from this peer. Start at 1 to 376 * permit self-announcement. */ 377 double m_addr_token_bucket GUARDED_BY(NetEventsInterface::g_msgproc_mutex){1.0}; 378 /** When m_addr_token_bucket was last updated */ 379 std::chrono::microseconds m_addr_token_timestamp GUARDED_BY(NetEventsInterface::g_msgproc_mutex){GetTime<std::chrono::microseconds>()}; 380 /** Total number of addresses that were dropped due to rate limiting. */ 381 std::atomic<uint64_t> m_addr_rate_limited{0}; 382 /** Total number of addresses that were processed (excludes rate-limited ones). */ 383 std::atomic<uint64_t> m_addr_processed{0}; 384 385 /** Whether we've sent this peer a getheaders in response to an inv prior to initial-headers-sync completing */ 386 bool m_inv_triggered_getheaders_before_sync GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false}; 387 388 /** Protects m_getdata_requests **/ 389 Mutex m_getdata_requests_mutex; 390 /** Work queue of items requested by this peer **/ 391 std::deque<CInv> m_getdata_requests GUARDED_BY(m_getdata_requests_mutex); 392 393 /** Time of the last getheaders message to this peer */ 394 NodeClock::time_point m_last_getheaders_timestamp GUARDED_BY(NetEventsInterface::g_msgproc_mutex){}; 395 396 /** Protects m_headers_sync **/ 397 Mutex m_headers_sync_mutex; 398 /** Headers-sync state for this peer (eg for initial sync, or syncing large 399 * reorgs) **/ 400 std::unique_ptr<HeadersSyncState> m_headers_sync PT_GUARDED_BY(m_headers_sync_mutex) GUARDED_BY(m_headers_sync_mutex) {}; 401 402 /** Whether we've sent our peer a sendheaders message. **/ 403 std::atomic<bool> m_sent_sendheaders{false}; 404 405 /** When to potentially disconnect peer for stalling headers download */ 406 std::chrono::microseconds m_headers_sync_timeout GUARDED_BY(NetEventsInterface::g_msgproc_mutex){0us}; 407 408 /** Whether this peer wants invs or headers (when possible) for block announcements */ 409 bool m_prefers_headers GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false}; 410 411 /** Time offset computed during the version handshake based on the 412 * timestamp the peer sent in the version message. */ 413 std::atomic<std::chrono::seconds> m_time_offset{0s}; 414 415 explicit Peer(NodeId id, ServiceFlags our_services, bool is_inbound) 416 : m_id{id} 417 , m_our_services{our_services} 418 , m_is_inbound{is_inbound} 419 {} 420 421 private: 422 mutable Mutex m_tx_relay_mutex; 423 424 /** Transaction relay data. May be a nullptr. */ 425 std::unique_ptr<TxRelay> m_tx_relay GUARDED_BY(m_tx_relay_mutex); 426 }; 427 428 using PeerRef = std::shared_ptr<Peer>; 429 430 /** 431 * Maintain validation-specific state about nodes, protected by cs_main, instead 432 * by CNode's own locks. This simplifies asynchronous operation, where 433 * processing of incoming data is done after the ProcessMessage call returns, 434 * and we're no longer holding the node's locks. 435 */ 436 struct CNodeState { 437 //! The best known block we know this peer has announced. 438 const CBlockIndex* pindexBestKnownBlock{nullptr}; 439 //! The hash of the last unknown block this peer has announced. 440 uint256 hashLastUnknownBlock{}; 441 //! The last full block we both have. 442 const CBlockIndex* pindexLastCommonBlock{nullptr}; 443 //! The best header we have sent our peer. 444 const CBlockIndex* pindexBestHeaderSent{nullptr}; 445 //! Whether we've started headers synchronization with this peer. 446 bool fSyncStarted{false}; 447 //! Since when we're stalling block download progress (in microseconds), or 0. 448 std::chrono::microseconds m_stalling_since{0us}; 449 std::list<QueuedBlock> vBlocksInFlight; 450 //! When the first entry in vBlocksInFlight started downloading. Don't care when vBlocksInFlight is empty. 451 std::chrono::microseconds m_downloading_since{0us}; 452 //! Whether we consider this a preferred download peer. 453 bool fPreferredDownload{false}; 454 /** Whether this peer wants invs or cmpctblocks (when possible) for block announcements. */ 455 bool m_requested_hb_cmpctblocks{false}; 456 /** Whether this peer will send us cmpctblocks if we request them. */ 457 bool m_provides_cmpctblocks{false}; 458 459 /** State used to enforce CHAIN_SYNC_TIMEOUT and EXTRA_PEER_CHECK_INTERVAL logic. 460 * 461 * Both are only in effect for outbound, non-manual, non-protected connections. 462 * Any peer protected (m_protect = true) is not chosen for eviction. A peer is 463 * marked as protected if all of these are true: 464 * - its connection type is IsBlockOnlyConn() == false 465 * - it gave us a valid connecting header 466 * - we haven't reached MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT yet 467 * - its chain tip has at least as much work as ours 468 * 469 * CHAIN_SYNC_TIMEOUT: if a peer's best known block has less work than our tip, 470 * set a timeout CHAIN_SYNC_TIMEOUT in the future: 471 * - If at timeout their best known block now has more work than our tip 472 * when the timeout was set, then either reset the timeout or clear it 473 * (after comparing against our current tip's work) 474 * - If at timeout their best known block still has less work than our 475 * tip did when the timeout was set, then send a getheaders message, 476 * and set a shorter timeout, HEADERS_RESPONSE_TIME seconds in future. 477 * If their best known block is still behind when that new timeout is 478 * reached, disconnect. 479 * 480 * EXTRA_PEER_CHECK_INTERVAL: after each interval, if we have too many outbound peers, 481 * drop the outbound one that least recently announced us a new block. 482 */ 483 struct ChainSyncTimeoutState { 484 //! A timeout used for checking whether our peer has sufficiently synced 485 std::chrono::seconds m_timeout{0s}; 486 //! A header with the work we require on our peer's chain 487 const CBlockIndex* m_work_header{nullptr}; 488 //! After timeout is reached, set to true after sending getheaders 489 bool m_sent_getheaders{false}; 490 //! Whether this peer is protected from disconnection due to a bad/slow chain 491 bool m_protect{false}; 492 }; 493 494 ChainSyncTimeoutState m_chain_sync; 495 496 //! Time of last new block announcement 497 int64_t m_last_block_announcement{0}; 498 }; 499 500 class PeerManagerImpl final : public PeerManager 501 { 502 public: 503 PeerManagerImpl(CConnman& connman, AddrMan& addrman, 504 BanMan* banman, ChainstateManager& chainman, 505 CTxMemPool& pool, node::Warnings& warnings, Options opts); 506 507 /** Overridden from CValidationInterface. */ 508 void ActiveTipChange(const CBlockIndex& new_tip, bool) override 509 EXCLUSIVE_LOCKS_REQUIRED(!m_tx_download_mutex); 510 void BlockConnected(ChainstateRole role, const std::shared_ptr<const CBlock>& pblock, const CBlockIndex* pindexConnected) override 511 EXCLUSIVE_LOCKS_REQUIRED(!m_tx_download_mutex); 512 void BlockDisconnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex* pindex) override 513 EXCLUSIVE_LOCKS_REQUIRED(!m_tx_download_mutex); 514 void UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) override 515 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 516 void BlockChecked(const CBlock& block, const BlockValidationState& state) override 517 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 518 void NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& pblock) override 519 EXCLUSIVE_LOCKS_REQUIRED(!m_most_recent_block_mutex); 520 521 /** Implement NetEventsInterface */ 522 void InitializeNode(const CNode& node, ServiceFlags our_services) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_tx_download_mutex); 523 void FinalizeNode(const CNode& node) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_headers_presync_mutex, !m_tx_download_mutex); 524 bool HasAllDesirableServiceFlags(ServiceFlags services) const override; 525 bool ProcessMessages(CNode* pfrom, std::atomic<bool>& interrupt) override 526 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_most_recent_block_mutex, !m_headers_presync_mutex, g_msgproc_mutex, !m_tx_download_mutex); 527 bool SendMessages(CNode* pto) override 528 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_most_recent_block_mutex, g_msgproc_mutex, !m_tx_download_mutex); 529 530 /** Implement PeerManager */ 531 void StartScheduledTasks(CScheduler& scheduler) override; 532 void CheckForStaleTipAndEvictPeers() override; 533 std::optional<std::string> FetchBlock(NodeId peer_id, const CBlockIndex& block_index) override 534 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 535 bool GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats) const override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 536 std::vector<TxOrphanage::OrphanTxBase> GetOrphanTransactions() override EXCLUSIVE_LOCKS_REQUIRED(!m_tx_download_mutex); 537 PeerManagerInfo GetInfo() const override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 538 void SendPings() override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 539 void RelayTransaction(const uint256& txid, const uint256& wtxid) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 540 void SetBestBlock(int height, std::chrono::seconds time) override 541 { 542 m_best_height = height; 543 m_best_block_time = time; 544 }; 545 void UnitTestMisbehaving(NodeId peer_id) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex) { Misbehaving(*Assert(GetPeerRef(peer_id)), ""); }; 546 void ProcessMessage(CNode& pfrom, const std::string& msg_type, DataStream& vRecv, 547 const std::chrono::microseconds time_received, const std::atomic<bool>& interruptMsgProc) override 548 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_most_recent_block_mutex, !m_headers_presync_mutex, g_msgproc_mutex, !m_tx_download_mutex); 549 void UpdateLastBlockAnnounceTime(NodeId node, int64_t time_in_seconds) override; 550 ServiceFlags GetDesirableServiceFlags(ServiceFlags services) const override; 551 552 private: 553 /** Consider evicting an outbound peer based on the amount of time they've been behind our tip */ 554 void ConsiderEviction(CNode& pto, Peer& peer, std::chrono::seconds time_in_seconds) EXCLUSIVE_LOCKS_REQUIRED(cs_main, g_msgproc_mutex); 555 556 /** If we have extra outbound peers, try to disconnect the one with the oldest block announcement */ 557 void EvictExtraOutboundPeers(std::chrono::seconds now) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 558 559 /** Retrieve unbroadcast transactions from the mempool and reattempt sending to peers */ 560 void ReattemptInitialBroadcast(CScheduler& scheduler) EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 561 562 /** Get a shared pointer to the Peer object. 563 * May return an empty shared_ptr if the Peer object can't be found. */ 564 PeerRef GetPeerRef(NodeId id) const EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 565 566 /** Get a shared pointer to the Peer object and remove it from m_peer_map. 567 * May return an empty shared_ptr if the Peer object can't be found. */ 568 PeerRef RemovePeer(NodeId id) EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 569 570 /** Mark a peer as misbehaving, which will cause it to be disconnected and its 571 * address discouraged. */ 572 void Misbehaving(Peer& peer, const std::string& message); 573 574 /** 575 * Potentially mark a node discouraged based on the contents of a BlockValidationState object 576 * 577 * @param[in] via_compact_block this bool is passed in because net_processing should 578 * punish peers differently depending on whether the data was provided in a compact 579 * block message or not. If the compact block had a valid header, but contained invalid 580 * txs, the peer should not be punished. See BIP 152. 581 */ 582 void MaybePunishNodeForBlock(NodeId nodeid, const BlockValidationState& state, 583 bool via_compact_block, const std::string& message = "") 584 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 585 586 /** 587 * Potentially disconnect and discourage a node based on the contents of a TxValidationState object 588 */ 589 void MaybePunishNodeForTx(NodeId nodeid, const TxValidationState& state) 590 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex); 591 592 /** Maybe disconnect a peer and discourage future connections from its address. 593 * 594 * @param[in] pnode The node to check. 595 * @param[in] peer The peer object to check. 596 * @return True if the peer was marked for disconnection in this function 597 */ 598 bool MaybeDiscourageAndDisconnect(CNode& pnode, Peer& peer); 599 600 /** Handle a transaction whose result was not MempoolAcceptResult::ResultType::VALID. 601 * @param[in] first_time_failure Whether we should consider inserting into vExtraTxnForCompact, adding 602 * a new orphan to resolve, or looking for a package to submit. 603 * Set to true for transactions just received over p2p. 604 * Set to false if the tx has already been rejected before, 605 * e.g. is already in the orphanage, to avoid adding duplicate entries. 606 * Updates m_txrequest, m_lazy_recent_rejects, m_lazy_recent_rejects_reconsiderable, m_orphanage, and vExtraTxnForCompact. 607 * 608 * @returns a PackageToValidate if this transaction has a reconsiderable failure and an eligible package was found, 609 * or std::nullopt otherwise. 610 */ 611 std::optional<node::PackageToValidate> ProcessInvalidTx(NodeId nodeid, const CTransactionRef& tx, const TxValidationState& result, 612 bool first_time_failure) 613 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex, m_tx_download_mutex); 614 615 /** Handle a transaction whose result was MempoolAcceptResult::ResultType::VALID. 616 * Updates m_txrequest, m_orphanage, and vExtraTxnForCompact. Also queues the tx for relay. */ 617 void ProcessValidTx(NodeId nodeid, const CTransactionRef& tx, const std::list<CTransactionRef>& replaced_transactions) 618 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex, m_tx_download_mutex); 619 620 /** Handle the results of package validation: calls ProcessValidTx and ProcessInvalidTx for 621 * individual transactions, and caches rejection for the package as a group. 622 */ 623 void ProcessPackageResult(const node::PackageToValidate& package_to_validate, const PackageMempoolAcceptResult& package_result) 624 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex, m_tx_download_mutex); 625 626 /** 627 * Reconsider orphan transactions after a parent has been accepted to the mempool. 628 * 629 * @peer[in] peer The peer whose orphan transactions we will reconsider. Generally only 630 * one orphan will be reconsidered on each call of this function. If an 631 * accepted orphan has orphaned children, those will need to be 632 * reconsidered, creating more work, possibly for other peers. 633 * @return True if meaningful work was done (an orphan was accepted/rejected). 634 * If no meaningful work was done, then the work set for this peer 635 * will be empty. 636 */ 637 bool ProcessOrphanTx(Peer& peer) 638 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex, !m_tx_download_mutex); 639 640 /** Process a single headers message from a peer. 641 * 642 * @param[in] pfrom CNode of the peer 643 * @param[in] peer The peer sending us the headers 644 * @param[in] headers The headers received. Note that this may be modified within ProcessHeadersMessage. 645 * @param[in] via_compact_block Whether this header came in via compact block handling. 646 */ 647 void ProcessHeadersMessage(CNode& pfrom, Peer& peer, 648 std::vector<CBlockHeader>&& headers, 649 bool via_compact_block) 650 EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_headers_presync_mutex, g_msgproc_mutex); 651 /** Various helpers for headers processing, invoked by ProcessHeadersMessage() */ 652 /** Return true if headers are continuous and have valid proof-of-work (DoS points assigned on failure) */ 653 bool CheckHeadersPoW(const std::vector<CBlockHeader>& headers, const Consensus::Params& consensusParams, Peer& peer); 654 /** Calculate an anti-DoS work threshold for headers chains */ 655 arith_uint256 GetAntiDoSWorkThreshold(); 656 /** Deal with state tracking and headers sync for peers that send 657 * non-connecting headers (this can happen due to BIP 130 headers 658 * announcements for blocks interacting with the 2hr (MAX_FUTURE_BLOCK_TIME) rule). */ 659 void HandleUnconnectingHeaders(CNode& pfrom, Peer& peer, const std::vector<CBlockHeader>& headers) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 660 /** Return true if the headers connect to each other, false otherwise */ 661 bool CheckHeadersAreContinuous(const std::vector<CBlockHeader>& headers) const; 662 /** Try to continue a low-work headers sync that has already begun. 663 * Assumes the caller has already verified the headers connect, and has 664 * checked that each header satisfies the proof-of-work target included in 665 * the header. 666 * @param[in] peer The peer we're syncing with. 667 * @param[in] pfrom CNode of the peer 668 * @param[in,out] headers The headers to be processed. 669 * @return True if the passed in headers were successfully processed 670 * as the continuation of a low-work headers sync in progress; 671 * false otherwise. 672 * If false, the passed in headers will be returned back to 673 * the caller. 674 * If true, the returned headers may be empty, indicating 675 * there is no more work for the caller to do; or the headers 676 * may be populated with entries that have passed anti-DoS 677 * checks (and therefore may be validated for block index 678 * acceptance by the caller). 679 */ 680 bool IsContinuationOfLowWorkHeadersSync(Peer& peer, CNode& pfrom, 681 std::vector<CBlockHeader>& headers) 682 EXCLUSIVE_LOCKS_REQUIRED(peer.m_headers_sync_mutex, !m_headers_presync_mutex, g_msgproc_mutex); 683 /** Check work on a headers chain to be processed, and if insufficient, 684 * initiate our anti-DoS headers sync mechanism. 685 * 686 * @param[in] peer The peer whose headers we're processing. 687 * @param[in] pfrom CNode of the peer 688 * @param[in] chain_start_header Where these headers connect in our index. 689 * @param[in,out] headers The headers to be processed. 690 * 691 * @return True if chain was low work (headers will be empty after 692 * calling); false otherwise. 693 */ 694 bool TryLowWorkHeadersSync(Peer& peer, CNode& pfrom, 695 const CBlockIndex* chain_start_header, 696 std::vector<CBlockHeader>& headers) 697 EXCLUSIVE_LOCKS_REQUIRED(!peer.m_headers_sync_mutex, !m_peer_mutex, !m_headers_presync_mutex, g_msgproc_mutex); 698 699 /** Return true if the given header is an ancestor of 700 * m_chainman.m_best_header or our current tip */ 701 bool IsAncestorOfBestHeaderOrTip(const CBlockIndex* header) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 702 703 /** Request further headers from this peer with a given locator. 704 * We don't issue a getheaders message if we have a recent one outstanding. 705 * This returns true if a getheaders is actually sent, and false otherwise. 706 */ 707 bool MaybeSendGetHeaders(CNode& pfrom, const CBlockLocator& locator, Peer& peer) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 708 /** Potentially fetch blocks from this peer upon receipt of a new headers tip */ 709 void HeadersDirectFetchBlocks(CNode& pfrom, const Peer& peer, const CBlockIndex& last_header); 710 /** Update peer state based on received headers message */ 711 void UpdatePeerStateForReceivedHeaders(CNode& pfrom, Peer& peer, const CBlockIndex& last_header, bool received_new_header, bool may_have_more_headers) 712 EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 713 714 void SendBlockTransactions(CNode& pfrom, Peer& peer, const CBlock& block, const BlockTransactionsRequest& req); 715 716 /** Send a message to a peer */ 717 void PushMessage(CNode& node, CSerializedNetMsg&& msg) const { m_connman.PushMessage(&node, std::move(msg)); } 718 template <typename... Args> 719 void MakeAndPushMessage(CNode& node, std::string msg_type, Args&&... args) const 720 { 721 m_connman.PushMessage(&node, NetMsg::Make(std::move(msg_type), std::forward<Args>(args)...)); 722 } 723 724 /** Send a version message to a peer */ 725 void PushNodeVersion(CNode& pnode, const Peer& peer); 726 727 /** Send a ping message every PING_INTERVAL or if requested via RPC. May 728 * mark the peer to be disconnected if a ping has timed out. 729 * We use mockable time for ping timeouts, so setmocktime may cause pings 730 * to time out. */ 731 void MaybeSendPing(CNode& node_to, Peer& peer, std::chrono::microseconds now); 732 733 /** Send `addr` messages on a regular schedule. */ 734 void MaybeSendAddr(CNode& node, Peer& peer, std::chrono::microseconds current_time) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 735 736 /** Send a single `sendheaders` message, after we have completed headers sync with a peer. */ 737 void MaybeSendSendHeaders(CNode& node, Peer& peer) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 738 739 /** Relay (gossip) an address to a few randomly chosen nodes. 740 * 741 * @param[in] originator The id of the peer that sent us the address. We don't want to relay it back. 742 * @param[in] addr Address to relay. 743 * @param[in] fReachable Whether the address' network is reachable. We relay unreachable 744 * addresses less. 745 */ 746 void RelayAddress(NodeId originator, const CAddress& addr, bool fReachable) EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex); 747 748 /** Send `feefilter` message. */ 749 void MaybeSendFeefilter(CNode& node, Peer& peer, std::chrono::microseconds current_time) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 750 751 FastRandomContext m_rng GUARDED_BY(NetEventsInterface::g_msgproc_mutex); 752 753 FeeFilterRounder m_fee_filter_rounder GUARDED_BY(NetEventsInterface::g_msgproc_mutex); 754 755 const CChainParams& m_chainparams; 756 CConnman& m_connman; 757 AddrMan& m_addrman; 758 /** Pointer to this node's banman. May be nullptr - check existence before dereferencing. */ 759 BanMan* const m_banman; 760 ChainstateManager& m_chainman; 761 CTxMemPool& m_mempool; 762 763 /** Synchronizes tx download including TxRequestTracker, rejection filters, and TxOrphanage. 764 * Lock invariants: 765 * - A txhash (txid or wtxid) in m_txrequest is not also in m_orphanage. 766 * - A txhash (txid or wtxid) in m_txrequest is not also in m_lazy_recent_rejects. 767 * - A txhash (txid or wtxid) in m_txrequest is not also in m_lazy_recent_rejects_reconsiderable. 768 * - A txhash (txid or wtxid) in m_txrequest is not also in m_lazy_recent_confirmed_transactions. 769 * - Each data structure's limits hold (m_orphanage max size, m_txrequest per-peer limits, etc). 770 */ 771 Mutex m_tx_download_mutex ACQUIRED_BEFORE(m_mempool.cs); 772 node::TxDownloadManager m_txdownloadman GUARDED_BY(m_tx_download_mutex); 773 774 std::unique_ptr<TxReconciliationTracker> m_txreconciliation; 775 776 /** The height of the best chain */ 777 std::atomic<int> m_best_height{-1}; 778 /** The time of the best chain tip block */ 779 std::atomic<std::chrono::seconds> m_best_block_time{0s}; 780 781 /** Next time to check for stale tip */ 782 std::chrono::seconds m_stale_tip_check_time GUARDED_BY(cs_main){0s}; 783 784 node::Warnings& m_warnings; 785 TimeOffsets m_outbound_time_offsets{m_warnings}; 786 787 const Options m_opts; 788 789 bool RejectIncomingTxs(const CNode& peer) const; 790 791 /** Whether we've completed initial sync yet, for determining when to turn 792 * on extra block-relay-only peers. */ 793 bool m_initial_sync_finished GUARDED_BY(cs_main){false}; 794 795 /** Protects m_peer_map. This mutex must not be locked while holding a lock 796 * on any of the mutexes inside a Peer object. */ 797 mutable Mutex m_peer_mutex; 798 /** 799 * Map of all Peer objects, keyed by peer id. This map is protected 800 * by the m_peer_mutex. Once a shared pointer reference is 801 * taken, the lock may be released. Individual fields are protected by 802 * their own locks. 803 */ 804 std::map<NodeId, PeerRef> m_peer_map GUARDED_BY(m_peer_mutex); 805 806 /** Map maintaining per-node state. */ 807 std::map<NodeId, CNodeState> m_node_states GUARDED_BY(cs_main); 808 809 /** Get a pointer to a const CNodeState, used when not mutating the CNodeState object. */ 810 const CNodeState* State(NodeId pnode) const EXCLUSIVE_LOCKS_REQUIRED(cs_main); 811 /** Get a pointer to a mutable CNodeState. */ 812 CNodeState* State(NodeId pnode) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 813 814 uint32_t GetFetchFlags(const Peer& peer) const; 815 816 std::atomic<std::chrono::microseconds> m_next_inv_to_inbounds{0us}; 817 818 /** Number of nodes with fSyncStarted. */ 819 int nSyncStarted GUARDED_BY(cs_main) = 0; 820 821 /** Hash of the last block we received via INV */ 822 uint256 m_last_block_inv_triggering_headers_sync GUARDED_BY(g_msgproc_mutex){}; 823 824 /** 825 * Sources of received blocks, saved to be able punish them when processing 826 * happens afterwards. 827 * Set mapBlockSource[hash].second to false if the node should not be 828 * punished if the block is invalid. 829 */ 830 std::map<uint256, std::pair<NodeId, bool>> mapBlockSource GUARDED_BY(cs_main); 831 832 /** Number of peers with wtxid relay. */ 833 std::atomic<int> m_wtxid_relay_peers{0}; 834 835 /** Number of outbound peers with m_chain_sync.m_protect. */ 836 int m_outbound_peers_with_protect_from_disconnect GUARDED_BY(cs_main) = 0; 837 838 /** Number of preferable block download peers. */ 839 int m_num_preferred_download_peers GUARDED_BY(cs_main){0}; 840 841 /** Stalling timeout for blocks in IBD */ 842 std::atomic<std::chrono::seconds> m_block_stalling_timeout{BLOCK_STALLING_TIMEOUT_DEFAULT}; 843 844 /** 845 * For sending `inv`s to inbound peers, we use a single (exponentially 846 * distributed) timer for all peers. If we used a separate timer for each 847 * peer, a spy node could make multiple inbound connections to us to 848 * accurately determine when we received the transaction (and potentially 849 * determine the transaction's origin). */ 850 std::chrono::microseconds NextInvToInbounds(std::chrono::microseconds now, 851 std::chrono::seconds average_interval) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 852 853 854 // All of the following cache a recent block, and are protected by m_most_recent_block_mutex 855 Mutex m_most_recent_block_mutex; 856 std::shared_ptr<const CBlock> m_most_recent_block GUARDED_BY(m_most_recent_block_mutex); 857 std::shared_ptr<const CBlockHeaderAndShortTxIDs> m_most_recent_compact_block GUARDED_BY(m_most_recent_block_mutex); 858 uint256 m_most_recent_block_hash GUARDED_BY(m_most_recent_block_mutex); 859 std::unique_ptr<const std::map<uint256, CTransactionRef>> m_most_recent_block_txs GUARDED_BY(m_most_recent_block_mutex); 860 861 // Data about the low-work headers synchronization, aggregated from all peers' HeadersSyncStates. 862 /** Mutex guarding the other m_headers_presync_* variables. */ 863 Mutex m_headers_presync_mutex; 864 /** A type to represent statistics about a peer's low-work headers sync. 865 * 866 * - The first field is the total verified amount of work in that synchronization. 867 * - The second is: 868 * - nullopt: the sync is in REDOWNLOAD phase (phase 2). 869 * - {height, timestamp}: the sync has the specified tip height and block timestamp (phase 1). 870 */ 871 using HeadersPresyncStats = std::pair<arith_uint256, std::optional<std::pair<int64_t, uint32_t>>>; 872 /** Statistics for all peers in low-work headers sync. */ 873 std::map<NodeId, HeadersPresyncStats> m_headers_presync_stats GUARDED_BY(m_headers_presync_mutex) {}; 874 /** The peer with the most-work entry in m_headers_presync_stats. */ 875 NodeId m_headers_presync_bestpeer GUARDED_BY(m_headers_presync_mutex) {-1}; 876 /** The m_headers_presync_stats improved, and needs signalling. */ 877 std::atomic_bool m_headers_presync_should_signal{false}; 878 879 /** Height of the highest block announced using BIP 152 high-bandwidth mode. */ 880 int m_highest_fast_announce GUARDED_BY(::cs_main){0}; 881 882 /** Have we requested this block from a peer */ 883 bool IsBlockRequested(const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 884 885 /** Have we requested this block from an outbound peer */ 886 bool IsBlockRequestedFromOutbound(const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main, !m_peer_mutex); 887 888 /** Remove this block from our tracked requested blocks. Called if: 889 * - the block has been received from a peer 890 * - the request for the block has timed out 891 * If "from_peer" is specified, then only remove the block if it is in 892 * flight from that peer (to avoid one peer's network traffic from 893 * affecting another's state). 894 */ 895 void RemoveBlockRequest(const uint256& hash, std::optional<NodeId> from_peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 896 897 /* Mark a block as in flight 898 * Returns false, still setting pit, if the block was already in flight from the same peer 899 * pit will only be valid as long as the same cs_main lock is being held 900 */ 901 bool BlockRequested(NodeId nodeid, const CBlockIndex& block, std::list<QueuedBlock>::iterator** pit = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 902 903 bool TipMayBeStale() EXCLUSIVE_LOCKS_REQUIRED(cs_main); 904 905 /** Update pindexLastCommonBlock and add not-in-flight missing successors to vBlocks, until it has 906 * at most count entries. 907 */ 908 void FindNextBlocksToDownload(const Peer& peer, unsigned int count, std::vector<const CBlockIndex*>& vBlocks, NodeId& nodeStaller) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 909 910 /** Request blocks for the background chainstate, if one is in use. */ 911 void TryDownloadingHistoricalBlocks(const Peer& peer, unsigned int count, std::vector<const CBlockIndex*>& vBlocks, const CBlockIndex* from_tip, const CBlockIndex* target_block) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 912 913 /** 914 * \brief Find next blocks to download from a peer after a starting block. 915 * 916 * \param vBlocks Vector of blocks to download which will be appended to. 917 * \param peer Peer which blocks will be downloaded from. 918 * \param state Pointer to the state of the peer. 919 * \param pindexWalk Pointer to the starting block to add to vBlocks. 920 * \param count Maximum number of blocks to allow in vBlocks. No more 921 * blocks will be added if it reaches this size. 922 * \param nWindowEnd Maximum height of blocks to allow in vBlocks. No 923 * blocks will be added above this height. 924 * \param activeChain Optional pointer to a chain to compare against. If 925 * provided, any next blocks which are already contained 926 * in this chain will not be appended to vBlocks, but 927 * instead will be used to update the 928 * state->pindexLastCommonBlock pointer. 929 * \param nodeStaller Optional pointer to a NodeId variable that will receive 930 * the ID of another peer that might be causing this peer 931 * to stall. This is set to the ID of the peer which 932 * first requested the first in-flight block in the 933 * download window. It is only set if vBlocks is empty at 934 * the end of this function call and if increasing 935 * nWindowEnd by 1 would cause it to be non-empty (which 936 * indicates the download might be stalled because every 937 * block in the window is in flight and no other peer is 938 * trying to download the next block). 939 */ 940 void FindNextBlocks(std::vector<const CBlockIndex*>& vBlocks, const Peer& peer, CNodeState *state, const CBlockIndex *pindexWalk, unsigned int count, int nWindowEnd, const CChain* activeChain=nullptr, NodeId* nodeStaller=nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 941 942 /* Multimap used to preserve insertion order */ 943 typedef std::multimap<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator>> BlockDownloadMap; 944 BlockDownloadMap mapBlocksInFlight GUARDED_BY(cs_main); 945 946 /** When our tip was last updated. */ 947 std::atomic<std::chrono::seconds> m_last_tip_update{0s}; 948 949 /** Determine whether or not a peer can request a transaction, and return it (or nullptr if not found or not allowed). */ 950 CTransactionRef FindTxForGetData(const Peer::TxRelay& tx_relay, const GenTxid& gtxid) 951 EXCLUSIVE_LOCKS_REQUIRED(!m_most_recent_block_mutex, NetEventsInterface::g_msgproc_mutex); 952 953 void ProcessGetData(CNode& pfrom, Peer& peer, const std::atomic<bool>& interruptMsgProc) 954 EXCLUSIVE_LOCKS_REQUIRED(!m_most_recent_block_mutex, peer.m_getdata_requests_mutex, NetEventsInterface::g_msgproc_mutex) 955 LOCKS_EXCLUDED(::cs_main); 956 957 /** Process a new block. Perform any post-processing housekeeping */ 958 void ProcessBlock(CNode& node, const std::shared_ptr<const CBlock>& block, bool force_processing, bool min_pow_checked); 959 960 /** Process compact block txns */ 961 void ProcessCompactBlockTxns(CNode& pfrom, Peer& peer, const BlockTransactions& block_transactions) 962 EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex, !m_most_recent_block_mutex); 963 964 /** 965 * When a peer sends us a valid block, instruct it to announce blocks to us 966 * using CMPCTBLOCK if possible by adding its nodeid to the end of 967 * lNodesAnnouncingHeaderAndIDs, and keeping that list under a certain size by 968 * removing the first element if necessary. 969 */ 970 void MaybeSetPeerAsAnnouncingHeaderAndIDs(NodeId nodeid) EXCLUSIVE_LOCKS_REQUIRED(cs_main, !m_peer_mutex); 971 972 /** Stack of nodes which we have set to announce using compact blocks */ 973 std::list<NodeId> lNodesAnnouncingHeaderAndIDs GUARDED_BY(cs_main); 974 975 /** Number of peers from which we're downloading blocks. */ 976 int m_peers_downloading_from GUARDED_BY(cs_main) = 0; 977 978 void AddToCompactExtraTransactions(const CTransactionRef& tx) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 979 980 /** Orphan/conflicted/etc transactions that are kept for compact block reconstruction. 981 * The last -blockreconstructionextratxn/DEFAULT_BLOCK_RECONSTRUCTION_EXTRA_TXN of 982 * these are kept in a ring buffer */ 983 std::vector<CTransactionRef> vExtraTxnForCompact GUARDED_BY(g_msgproc_mutex); 984 /** Offset into vExtraTxnForCompact to insert the next tx */ 985 size_t vExtraTxnForCompactIt GUARDED_BY(g_msgproc_mutex) = 0; 986 987 /** Check whether the last unknown block a peer advertised is not yet known. */ 988 void ProcessBlockAvailability(NodeId nodeid) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 989 /** Update tracking information about which blocks a peer is assumed to have. */ 990 void UpdateBlockAvailability(NodeId nodeid, const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 991 bool CanDirectFetch() EXCLUSIVE_LOCKS_REQUIRED(cs_main); 992 993 /** 994 * Estimates the distance, in blocks, between the best-known block and the network chain tip. 995 * Utilizes the best-block time and the chainparams blocks spacing to approximate it. 996 */ 997 int64_t ApproximateBestBlockDepth() const; 998 999 /** 1000 * To prevent fingerprinting attacks, only send blocks/headers outside of 1001 * the active chain if they are no more than a month older (both in time, 1002 * and in best equivalent proof of work) than the best header chain we know 1003 * about and we fully-validated them at some point. 1004 */ 1005 bool BlockRequestAllowed(const CBlockIndex* pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 1006 bool AlreadyHaveBlock(const uint256& block_hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main); 1007 void ProcessGetBlockData(CNode& pfrom, Peer& peer, const CInv& inv) 1008 EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex, !m_most_recent_block_mutex); 1009 1010 /** 1011 * Validation logic for compact filters request handling. 1012 * 1013 * May disconnect from the peer in the case of a bad request. 1014 * 1015 * @param[in] node The node that we received the request from 1016 * @param[in] peer The peer that we received the request from 1017 * @param[in] filter_type The filter type the request is for. Must be basic filters. 1018 * @param[in] start_height The start height for the request 1019 * @param[in] stop_hash The stop_hash for the request 1020 * @param[in] max_height_diff The maximum number of items permitted to request, as specified in BIP 157 1021 * @param[out] stop_index The CBlockIndex for the stop_hash block, if the request can be serviced. 1022 * @param[out] filter_index The filter index, if the request can be serviced. 1023 * @return True if the request can be serviced. 1024 */ 1025 bool PrepareBlockFilterRequest(CNode& node, Peer& peer, 1026 BlockFilterType filter_type, uint32_t start_height, 1027 const uint256& stop_hash, uint32_t max_height_diff, 1028 const CBlockIndex*& stop_index, 1029 BlockFilterIndex*& filter_index); 1030 1031 /** 1032 * Handle a cfilters request. 1033 * 1034 * May disconnect from the peer in the case of a bad request. 1035 * 1036 * @param[in] node The node that we received the request from 1037 * @param[in] peer The peer that we received the request from 1038 * @param[in] vRecv The raw message received 1039 */ 1040 void ProcessGetCFilters(CNode& node, Peer& peer, DataStream& vRecv); 1041 1042 /** 1043 * Handle a cfheaders request. 1044 * 1045 * May disconnect from the peer in the case of a bad request. 1046 * 1047 * @param[in] node The node that we received the request from 1048 * @param[in] peer The peer that we received the request from 1049 * @param[in] vRecv The raw message received 1050 */ 1051 void ProcessGetCFHeaders(CNode& node, Peer& peer, DataStream& vRecv); 1052 1053 /** 1054 * Handle a getcfcheckpt request. 1055 * 1056 * May disconnect from the peer in the case of a bad request. 1057 * 1058 * @param[in] node The node that we received the request from 1059 * @param[in] peer The peer that we received the request from 1060 * @param[in] vRecv The raw message received 1061 */ 1062 void ProcessGetCFCheckPt(CNode& node, Peer& peer, DataStream& vRecv); 1063 1064 /** Checks if address relay is permitted with peer. If needed, initializes 1065 * the m_addr_known bloom filter and sets m_addr_relay_enabled to true. 1066 * 1067 * @return True if address relay is enabled with peer 1068 * False if address relay is disallowed 1069 */ 1070 bool SetupAddressRelay(const CNode& node, Peer& peer) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 1071 1072 void AddAddressKnown(Peer& peer, const CAddress& addr) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 1073 void PushAddress(Peer& peer, const CAddress& addr) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex); 1074 1075 void LogBlockHeader(const CBlockIndex& index, const CNode& peer, bool via_compact_block); 1076 }; 1077 1078 const CNodeState* PeerManagerImpl::State(NodeId pnode) const 1079 { 1080 std::map<NodeId, CNodeState>::const_iterator it = m_node_states.find(pnode); 1081 if (it == m_node_states.end()) 1082 return nullptr; 1083 return &it->second; 1084 } 1085 1086 CNodeState* PeerManagerImpl::State(NodeId pnode) 1087 { 1088 return const_cast<CNodeState*>(std::as_const(*this).State(pnode)); 1089 } 1090 1091 /** 1092 * Whether the peer supports the address. For example, a peer that does not 1093 * implement BIP155 cannot receive Tor v3 addresses because it requires 1094 * ADDRv2 (BIP155) encoding. 1095 */ 1096 static bool IsAddrCompatible(const Peer& peer, const CAddress& addr) 1097 { 1098 return peer.m_wants_addrv2 || addr.IsAddrV1Compatible(); 1099 } 1100 1101 void PeerManagerImpl::AddAddressKnown(Peer& peer, const CAddress& addr) 1102 { 1103 assert(peer.m_addr_known); 1104 peer.m_addr_known->insert(addr.GetKey()); 1105 } 1106 1107 void PeerManagerImpl::PushAddress(Peer& peer, const CAddress& addr) 1108 { 1109 // Known checking here is only to save space from duplicates. 1110 // Before sending, we'll filter it again for known addresses that were 1111 // added after addresses were pushed. 1112 assert(peer.m_addr_known); 1113 if (addr.IsValid() && !peer.m_addr_known->contains(addr.GetKey()) && IsAddrCompatible(peer, addr)) { 1114 if (peer.m_addrs_to_send.size() >= MAX_ADDR_TO_SEND) { 1115 peer.m_addrs_to_send[m_rng.randrange(peer.m_addrs_to_send.size())] = addr; 1116 } else { 1117 peer.m_addrs_to_send.push_back(addr); 1118 } 1119 } 1120 } 1121 1122 static void AddKnownTx(Peer& peer, const uint256& hash) 1123 { 1124 auto tx_relay = peer.GetTxRelay(); 1125 if (!tx_relay) return; 1126 1127 LOCK(tx_relay->m_tx_inventory_mutex); 1128 tx_relay->m_tx_inventory_known_filter.insert(hash); 1129 } 1130 1131 /** Whether this peer can serve us blocks. */ 1132 static bool CanServeBlocks(const Peer& peer) 1133 { 1134 return peer.m_their_services & (NODE_NETWORK|NODE_NETWORK_LIMITED); 1135 } 1136 1137 /** Whether this peer can only serve limited recent blocks (e.g. because 1138 * it prunes old blocks) */ 1139 static bool IsLimitedPeer(const Peer& peer) 1140 { 1141 return (!(peer.m_their_services & NODE_NETWORK) && 1142 (peer.m_their_services & NODE_NETWORK_LIMITED)); 1143 } 1144 1145 /** Whether this peer can serve us witness data */ 1146 static bool CanServeWitnesses(const Peer& peer) 1147 { 1148 return peer.m_their_services & NODE_WITNESS; 1149 } 1150 1151 std::chrono::microseconds PeerManagerImpl::NextInvToInbounds(std::chrono::microseconds now, 1152 std::chrono::seconds average_interval) 1153 { 1154 if (m_next_inv_to_inbounds.load() < now) { 1155 // If this function were called from multiple threads simultaneously 1156 // it would possible that both update the next send variable, and return a different result to their caller. 1157 // This is not possible in practice as only the net processing thread invokes this function. 1158 m_next_inv_to_inbounds = now + m_rng.rand_exp_duration(average_interval); 1159 } 1160 return m_next_inv_to_inbounds; 1161 } 1162 1163 bool PeerManagerImpl::IsBlockRequested(const uint256& hash) 1164 { 1165 return mapBlocksInFlight.count(hash); 1166 } 1167 1168 bool PeerManagerImpl::IsBlockRequestedFromOutbound(const uint256& hash) 1169 { 1170 for (auto range = mapBlocksInFlight.equal_range(hash); range.first != range.second; range.first++) { 1171 auto [nodeid, block_it] = range.first->second; 1172 PeerRef peer{GetPeerRef(nodeid)}; 1173 if (peer && !peer->m_is_inbound) return true; 1174 } 1175 1176 return false; 1177 } 1178 1179 void PeerManagerImpl::RemoveBlockRequest(const uint256& hash, std::optional<NodeId> from_peer) 1180 { 1181 auto range = mapBlocksInFlight.equal_range(hash); 1182 if (range.first == range.second) { 1183 // Block was not requested from any peer 1184 return; 1185 } 1186 1187 // We should not have requested too many of this block 1188 Assume(mapBlocksInFlight.count(hash) <= MAX_CMPCTBLOCKS_INFLIGHT_PER_BLOCK); 1189 1190 while (range.first != range.second) { 1191 const auto& [node_id, list_it]{range.first->second}; 1192 1193 if (from_peer && *from_peer != node_id) { 1194 range.first++; 1195 continue; 1196 } 1197 1198 CNodeState& state = *Assert(State(node_id)); 1199 1200 if (state.vBlocksInFlight.begin() == list_it) { 1201 // First block on the queue was received, update the start download time for the next one 1202 state.m_downloading_since = std::max(state.m_downloading_since, GetTime<std::chrono::microseconds>()); 1203 } 1204 state.vBlocksInFlight.erase(list_it); 1205 1206 if (state.vBlocksInFlight.empty()) { 1207 // Last validated block on the queue for this peer was received. 1208 m_peers_downloading_from--; 1209 } 1210 state.m_stalling_since = 0us; 1211 1212 range.first = mapBlocksInFlight.erase(range.first); 1213 } 1214 } 1215 1216 bool PeerManagerImpl::BlockRequested(NodeId nodeid, const CBlockIndex& block, std::list<QueuedBlock>::iterator** pit) 1217 { 1218 const uint256& hash{block.GetBlockHash()}; 1219 1220 CNodeState *state = State(nodeid); 1221 assert(state != nullptr); 1222 1223 Assume(mapBlocksInFlight.count(hash) <= MAX_CMPCTBLOCKS_INFLIGHT_PER_BLOCK); 1224 1225 // Short-circuit most stuff in case it is from the same node 1226 for (auto range = mapBlocksInFlight.equal_range(hash); range.first != range.second; range.first++) { 1227 if (range.first->second.first == nodeid) { 1228 if (pit) { 1229 *pit = &range.first->second.second; 1230 } 1231 return false; 1232 } 1233 } 1234 1235 // Make sure it's not being fetched already from same peer. 1236 RemoveBlockRequest(hash, nodeid); 1237 1238 std::list<QueuedBlock>::iterator it = state->vBlocksInFlight.insert(state->vBlocksInFlight.end(), 1239 {&block, std::unique_ptr<PartiallyDownloadedBlock>(pit ? new PartiallyDownloadedBlock(&m_mempool) : nullptr)}); 1240 if (state->vBlocksInFlight.size() == 1) { 1241 // We're starting a block download (batch) from this peer. 1242 state->m_downloading_since = GetTime<std::chrono::microseconds>(); 1243 m_peers_downloading_from++; 1244 } 1245 auto itInFlight = mapBlocksInFlight.insert(std::make_pair(hash, std::make_pair(nodeid, it))); 1246 if (pit) { 1247 *pit = &itInFlight->second.second; 1248 } 1249 return true; 1250 } 1251 1252 void PeerManagerImpl::MaybeSetPeerAsAnnouncingHeaderAndIDs(NodeId nodeid) 1253 { 1254 AssertLockHeld(cs_main); 1255 1256 // When in -blocksonly mode, never request high-bandwidth mode from peers. Our 1257 // mempool will not contain the transactions necessary to reconstruct the 1258 // compact block. 1259 if (m_opts.ignore_incoming_txs) return; 1260 1261 CNodeState* nodestate = State(nodeid); 1262 PeerRef peer{GetPeerRef(nodeid)}; 1263 if (!nodestate || !nodestate->m_provides_cmpctblocks) { 1264 // Don't request compact blocks if the peer has not signalled support 1265 return; 1266 } 1267 1268 int num_outbound_hb_peers = 0; 1269 for (std::list<NodeId>::iterator it = lNodesAnnouncingHeaderAndIDs.begin(); it != lNodesAnnouncingHeaderAndIDs.end(); it++) { 1270 if (*it == nodeid) { 1271 lNodesAnnouncingHeaderAndIDs.erase(it); 1272 lNodesAnnouncingHeaderAndIDs.push_back(nodeid); 1273 return; 1274 } 1275 PeerRef peer_ref{GetPeerRef(*it)}; 1276 if (peer_ref && !peer_ref->m_is_inbound) ++num_outbound_hb_peers; 1277 } 1278 if (peer && peer->m_is_inbound) { 1279 // If we're adding an inbound HB peer, make sure we're not removing 1280 // our last outbound HB peer in the process. 1281 if (lNodesAnnouncingHeaderAndIDs.size() >= 3 && num_outbound_hb_peers == 1) { 1282 PeerRef remove_peer{GetPeerRef(lNodesAnnouncingHeaderAndIDs.front())}; 1283 if (remove_peer && !remove_peer->m_is_inbound) { 1284 // Put the HB outbound peer in the second slot, so that it 1285 // doesn't get removed. 1286 std::swap(lNodesAnnouncingHeaderAndIDs.front(), *std::next(lNodesAnnouncingHeaderAndIDs.begin())); 1287 } 1288 } 1289 } 1290 m_connman.ForNode(nodeid, [this](CNode* pfrom) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) { 1291 AssertLockHeld(::cs_main); 1292 if (lNodesAnnouncingHeaderAndIDs.size() >= 3) { 1293 // As per BIP152, we only get 3 of our peers to announce 1294 // blocks using compact encodings. 1295 m_connman.ForNode(lNodesAnnouncingHeaderAndIDs.front(), [this](CNode* pnodeStop){ 1296 MakeAndPushMessage(*pnodeStop, NetMsgType::SENDCMPCT, /*high_bandwidth=*/false, /*version=*/CMPCTBLOCKS_VERSION); 1297 // save BIP152 bandwidth state: we select peer to be low-bandwidth 1298 pnodeStop->m_bip152_highbandwidth_to = false; 1299 return true; 1300 }); 1301 lNodesAnnouncingHeaderAndIDs.pop_front(); 1302 } 1303 MakeAndPushMessage(*pfrom, NetMsgType::SENDCMPCT, /*high_bandwidth=*/true, /*version=*/CMPCTBLOCKS_VERSION); 1304 // save BIP152 bandwidth state: we select peer to be high-bandwidth 1305 pfrom->m_bip152_highbandwidth_to = true; 1306 lNodesAnnouncingHeaderAndIDs.push_back(pfrom->GetId()); 1307 return true; 1308 }); 1309 } 1310 1311 bool PeerManagerImpl::TipMayBeStale() 1312 { 1313 AssertLockHeld(cs_main); 1314 const Consensus::Params& consensusParams = m_chainparams.GetConsensus(); 1315 if (m_last_tip_update.load() == 0s) { 1316 m_last_tip_update = GetTime<std::chrono::seconds>(); 1317 } 1318 return m_last_tip_update.load() < GetTime<std::chrono::seconds>() - std::chrono::seconds{consensusParams.nPowTargetSpacing * 3} && mapBlocksInFlight.empty(); 1319 } 1320 1321 int64_t PeerManagerImpl::ApproximateBestBlockDepth() const 1322 { 1323 return (GetTime<std::chrono::seconds>() - m_best_block_time.load()).count() / m_chainparams.GetConsensus().nPowTargetSpacing; 1324 } 1325 1326 bool PeerManagerImpl::CanDirectFetch() 1327 { 1328 return m_chainman.ActiveChain().Tip()->Time() > NodeClock::now() - m_chainparams.GetConsensus().PowTargetSpacing() * 20; 1329 } 1330 1331 static bool PeerHasHeader(CNodeState *state, const CBlockIndex *pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main) 1332 { 1333 if (state->pindexBestKnownBlock && pindex == state->pindexBestKnownBlock->GetAncestor(pindex->nHeight)) 1334 return true; 1335 if (state->pindexBestHeaderSent && pindex == state->pindexBestHeaderSent->GetAncestor(pindex->nHeight)) 1336 return true; 1337 return false; 1338 } 1339 1340 void PeerManagerImpl::ProcessBlockAvailability(NodeId nodeid) { 1341 CNodeState *state = State(nodeid); 1342 assert(state != nullptr); 1343 1344 if (!state->hashLastUnknownBlock.IsNull()) { 1345 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(state->hashLastUnknownBlock); 1346 if (pindex && pindex->nChainWork > 0) { 1347 if (state->pindexBestKnownBlock == nullptr || pindex->nChainWork >= state->pindexBestKnownBlock->nChainWork) { 1348 state->pindexBestKnownBlock = pindex; 1349 } 1350 state->hashLastUnknownBlock.SetNull(); 1351 } 1352 } 1353 } 1354 1355 void PeerManagerImpl::UpdateBlockAvailability(NodeId nodeid, const uint256 &hash) { 1356 CNodeState *state = State(nodeid); 1357 assert(state != nullptr); 1358 1359 ProcessBlockAvailability(nodeid); 1360 1361 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(hash); 1362 if (pindex && pindex->nChainWork > 0) { 1363 // An actually better block was announced. 1364 if (state->pindexBestKnownBlock == nullptr || pindex->nChainWork >= state->pindexBestKnownBlock->nChainWork) { 1365 state->pindexBestKnownBlock = pindex; 1366 } 1367 } else { 1368 // An unknown block was announced; just assume that the latest one is the best one. 1369 state->hashLastUnknownBlock = hash; 1370 } 1371 } 1372 1373 // Logic for calculating which blocks to download from a given peer, given our current tip. 1374 void PeerManagerImpl::FindNextBlocksToDownload(const Peer& peer, unsigned int count, std::vector<const CBlockIndex*>& vBlocks, NodeId& nodeStaller) 1375 { 1376 if (count == 0) 1377 return; 1378 1379 vBlocks.reserve(vBlocks.size() + count); 1380 CNodeState *state = State(peer.m_id); 1381 assert(state != nullptr); 1382 1383 // Make sure pindexBestKnownBlock is up to date, we'll need it. 1384 ProcessBlockAvailability(peer.m_id); 1385 1386 if (state->pindexBestKnownBlock == nullptr || state->pindexBestKnownBlock->nChainWork < m_chainman.ActiveChain().Tip()->nChainWork || state->pindexBestKnownBlock->nChainWork < m_chainman.MinimumChainWork()) { 1387 // This peer has nothing interesting. 1388 return; 1389 } 1390 1391 // When we sync with AssumeUtxo and discover the snapshot is not in the peer's best chain, abort: 1392 // We can't reorg to this chain due to missing undo data until the background sync has finished, 1393 // so downloading blocks from it would be futile. 1394 const CBlockIndex* snap_base{m_chainman.GetSnapshotBaseBlock()}; 1395 if (snap_base && state->pindexBestKnownBlock->GetAncestor(snap_base->nHeight) != snap_base) { 1396 LogDebug(BCLog::NET, "Not downloading blocks from peer=%d, which doesn't have the snapshot block in its best chain.\n", peer.m_id); 1397 return; 1398 } 1399 1400 // Bootstrap quickly by guessing a parent of our best tip is the forking point. 1401 // Guessing wrong in either direction is not a problem. 1402 // Also reset pindexLastCommonBlock after a snapshot was loaded, so that blocks after the snapshot will be prioritised for download. 1403 if (state->pindexLastCommonBlock == nullptr || 1404 (snap_base && state->pindexLastCommonBlock->nHeight < snap_base->nHeight)) { 1405 state->pindexLastCommonBlock = m_chainman.ActiveChain()[std::min(state->pindexBestKnownBlock->nHeight, m_chainman.ActiveChain().Height())]; 1406 } 1407 1408 // If the peer reorganized, our previous pindexLastCommonBlock may not be an ancestor 1409 // of its current tip anymore. Go back enough to fix that. 1410 state->pindexLastCommonBlock = LastCommonAncestor(state->pindexLastCommonBlock, state->pindexBestKnownBlock); 1411 if (state->pindexLastCommonBlock == state->pindexBestKnownBlock) 1412 return; 1413 1414 const CBlockIndex *pindexWalk = state->pindexLastCommonBlock; 1415 // Never fetch further than the best block we know the peer has, or more than BLOCK_DOWNLOAD_WINDOW + 1 beyond the last 1416 // linked block we have in common with this peer. The +1 is so we can detect stalling, namely if we would be able to 1417 // download that next block if the window were 1 larger. 1418 int nWindowEnd = state->pindexLastCommonBlock->nHeight + BLOCK_DOWNLOAD_WINDOW; 1419 1420 FindNextBlocks(vBlocks, peer, state, pindexWalk, count, nWindowEnd, &m_chainman.ActiveChain(), &nodeStaller); 1421 } 1422 1423 void PeerManagerImpl::TryDownloadingHistoricalBlocks(const Peer& peer, unsigned int count, std::vector<const CBlockIndex*>& vBlocks, const CBlockIndex *from_tip, const CBlockIndex* target_block) 1424 { 1425 Assert(from_tip); 1426 Assert(target_block); 1427 1428 if (vBlocks.size() >= count) { 1429 return; 1430 } 1431 1432 vBlocks.reserve(count); 1433 CNodeState *state = Assert(State(peer.m_id)); 1434 1435 if (state->pindexBestKnownBlock == nullptr || state->pindexBestKnownBlock->GetAncestor(target_block->nHeight) != target_block) { 1436 // This peer can't provide us the complete series of blocks leading up to the 1437 // assumeutxo snapshot base. 1438 // 1439 // Presumably this peer's chain has less work than our ActiveChain()'s tip, or else we 1440 // will eventually crash when we try to reorg to it. Let other logic 1441 // deal with whether we disconnect this peer. 1442 // 1443 // TODO at some point in the future, we might choose to request what blocks 1444 // this peer does have from the historical chain, despite it not having a 1445 // complete history beneath the snapshot base. 1446 return; 1447 } 1448 1449 FindNextBlocks(vBlocks, peer, state, from_tip, count, std::min<int>(from_tip->nHeight + BLOCK_DOWNLOAD_WINDOW, target_block->nHeight)); 1450 } 1451 1452 void PeerManagerImpl::FindNextBlocks(std::vector<const CBlockIndex*>& vBlocks, const Peer& peer, CNodeState *state, const CBlockIndex *pindexWalk, unsigned int count, int nWindowEnd, const CChain* activeChain, NodeId* nodeStaller) 1453 { 1454 std::vector<const CBlockIndex*> vToFetch; 1455 int nMaxHeight = std::min<int>(state->pindexBestKnownBlock->nHeight, nWindowEnd + 1); 1456 bool is_limited_peer = IsLimitedPeer(peer); 1457 NodeId waitingfor = -1; 1458 while (pindexWalk->nHeight < nMaxHeight) { 1459 // Read up to 128 (or more, if more blocks than that are needed) successors of pindexWalk (towards 1460 // pindexBestKnownBlock) into vToFetch. We fetch 128, because CBlockIndex::GetAncestor may be as expensive 1461 // as iterating over ~100 CBlockIndex* entries anyway. 1462 int nToFetch = std::min(nMaxHeight - pindexWalk->nHeight, std::max<int>(count - vBlocks.size(), 128)); 1463 vToFetch.resize(nToFetch); 1464 pindexWalk = state->pindexBestKnownBlock->GetAncestor(pindexWalk->nHeight + nToFetch); 1465 vToFetch[nToFetch - 1] = pindexWalk; 1466 for (unsigned int i = nToFetch - 1; i > 0; i--) { 1467 vToFetch[i - 1] = vToFetch[i]->pprev; 1468 } 1469 1470 // Iterate over those blocks in vToFetch (in forward direction), adding the ones that 1471 // are not yet downloaded and not in flight to vBlocks. In the meantime, update 1472 // pindexLastCommonBlock as long as all ancestors are already downloaded, or if it's 1473 // already part of our chain (and therefore don't need it even if pruned). 1474 for (const CBlockIndex* pindex : vToFetch) { 1475 if (!pindex->IsValid(BLOCK_VALID_TREE)) { 1476 // We consider the chain that this peer is on invalid. 1477 return; 1478 } 1479 1480 if (!CanServeWitnesses(peer) && DeploymentActiveAt(*pindex, m_chainman, Consensus::DEPLOYMENT_SEGWIT)) { 1481 // We wouldn't download this block or its descendants from this peer. 1482 return; 1483 } 1484 1485 if (pindex->nStatus & BLOCK_HAVE_DATA || (activeChain && activeChain->Contains(pindex))) { 1486 if (activeChain && pindex->HaveNumChainTxs()) { 1487 state->pindexLastCommonBlock = pindex; 1488 } 1489 continue; 1490 } 1491 1492 // Is block in-flight? 1493 if (IsBlockRequested(pindex->GetBlockHash())) { 1494 if (waitingfor == -1) { 1495 // This is the first already-in-flight block. 1496 waitingfor = mapBlocksInFlight.lower_bound(pindex->GetBlockHash())->second.first; 1497 } 1498 continue; 1499 } 1500 1501 // The block is not already downloaded, and not yet in flight. 1502 if (pindex->nHeight > nWindowEnd) { 1503 // We reached the end of the window. 1504 if (vBlocks.size() == 0 && waitingfor != peer.m_id) { 1505 // We aren't able to fetch anything, but we would be if the download window was one larger. 1506 if (nodeStaller) *nodeStaller = waitingfor; 1507 } 1508 return; 1509 } 1510 1511 // Don't request blocks that go further than what limited peers can provide 1512 if (is_limited_peer && (state->pindexBestKnownBlock->nHeight - pindex->nHeight >= static_cast<int>(NODE_NETWORK_LIMITED_MIN_BLOCKS) - 2 /* two blocks buffer for possible races */)) { 1513 continue; 1514 } 1515 1516 vBlocks.push_back(pindex); 1517 if (vBlocks.size() == count) { 1518 return; 1519 } 1520 } 1521 } 1522 } 1523 1524 } // namespace 1525 1526 void PeerManagerImpl::PushNodeVersion(CNode& pnode, const Peer& peer) 1527 { 1528 uint64_t my_services{peer.m_our_services}; 1529 const int64_t nTime{count_seconds(GetTime<std::chrono::seconds>())}; 1530 uint64_t nonce = pnode.GetLocalNonce(); 1531 const int nNodeStartingHeight{m_best_height}; 1532 NodeId nodeid = pnode.GetId(); 1533 CAddress addr = pnode.addr; 1534 1535 CService addr_you = addr.IsRoutable() && !IsProxy(addr) && addr.IsAddrV1Compatible() ? addr : CService(); 1536 uint64_t your_services{addr.nServices}; 1537 1538 const bool tx_relay{!RejectIncomingTxs(pnode)}; 1539 MakeAndPushMessage(pnode, NetMsgType::VERSION, PROTOCOL_VERSION, my_services, nTime, 1540 your_services, CNetAddr::V1(addr_you), // Together the pre-version-31402 serialization of CAddress "addrYou" (without nTime) 1541 my_services, CNetAddr::V1(CService{}), // Together the pre-version-31402 serialization of CAddress "addrMe" (without nTime) 1542 nonce, strSubVersion, nNodeStartingHeight, tx_relay); 1543 1544 if (fLogIPs) { 1545 LogDebug(BCLog::NET, "send version message: version %d, blocks=%d, them=%s, txrelay=%d, peer=%d\n", PROTOCOL_VERSION, nNodeStartingHeight, addr_you.ToStringAddrPort(), tx_relay, nodeid); 1546 } else { 1547 LogDebug(BCLog::NET, "send version message: version %d, blocks=%d, txrelay=%d, peer=%d\n", PROTOCOL_VERSION, nNodeStartingHeight, tx_relay, nodeid); 1548 } 1549 } 1550 1551 void PeerManagerImpl::UpdateLastBlockAnnounceTime(NodeId node, int64_t time_in_seconds) 1552 { 1553 LOCK(cs_main); 1554 CNodeState *state = State(node); 1555 if (state) state->m_last_block_announcement = time_in_seconds; 1556 } 1557 1558 void PeerManagerImpl::InitializeNode(const CNode& node, ServiceFlags our_services) 1559 { 1560 NodeId nodeid = node.GetId(); 1561 { 1562 LOCK(cs_main); // For m_node_states 1563 m_node_states.try_emplace(m_node_states.end(), nodeid); 1564 } 1565 WITH_LOCK(m_tx_download_mutex, m_txdownloadman.CheckIsEmpty(nodeid)); 1566 1567 if (NetPermissions::HasFlag(node.m_permission_flags, NetPermissionFlags::BloomFilter)) { 1568 our_services = static_cast<ServiceFlags>(our_services | NODE_BLOOM); 1569 } 1570 1571 PeerRef peer = std::make_shared<Peer>(nodeid, our_services, node.IsInboundConn()); 1572 { 1573 LOCK(m_peer_mutex); 1574 m_peer_map.emplace_hint(m_peer_map.end(), nodeid, peer); 1575 } 1576 } 1577 1578 void PeerManagerImpl::ReattemptInitialBroadcast(CScheduler& scheduler) 1579 { 1580 std::set<uint256> unbroadcast_txids = m_mempool.GetUnbroadcastTxs(); 1581 1582 for (const auto& txid : unbroadcast_txids) { 1583 CTransactionRef tx = m_mempool.get(txid); 1584 1585 if (tx != nullptr) { 1586 RelayTransaction(txid, tx->GetWitnessHash()); 1587 } else { 1588 m_mempool.RemoveUnbroadcastTx(txid, true); 1589 } 1590 } 1591 1592 // Schedule next run for 10-15 minutes in the future. 1593 // We add randomness on every cycle to avoid the possibility of P2P fingerprinting. 1594 const auto delta = 10min + FastRandomContext().randrange<std::chrono::milliseconds>(5min); 1595 scheduler.scheduleFromNow([&] { ReattemptInitialBroadcast(scheduler); }, delta); 1596 } 1597 1598 void PeerManagerImpl::FinalizeNode(const CNode& node) 1599 { 1600 NodeId nodeid = node.GetId(); 1601 { 1602 LOCK(cs_main); 1603 { 1604 // We remove the PeerRef from g_peer_map here, but we don't always 1605 // destruct the Peer. Sometimes another thread is still holding a 1606 // PeerRef, so the refcount is >= 1. Be careful not to do any 1607 // processing here that assumes Peer won't be changed before it's 1608 // destructed. 1609 PeerRef peer = RemovePeer(nodeid); 1610 assert(peer != nullptr); 1611 m_wtxid_relay_peers -= peer->m_wtxid_relay; 1612 assert(m_wtxid_relay_peers >= 0); 1613 } 1614 CNodeState *state = State(nodeid); 1615 assert(state != nullptr); 1616 1617 if (state->fSyncStarted) 1618 nSyncStarted--; 1619 1620 for (const QueuedBlock& entry : state->vBlocksInFlight) { 1621 auto range = mapBlocksInFlight.equal_range(entry.pindex->GetBlockHash()); 1622 while (range.first != range.second) { 1623 auto [node_id, list_it] = range.first->second; 1624 if (node_id != nodeid) { 1625 range.first++; 1626 } else { 1627 range.first = mapBlocksInFlight.erase(range.first); 1628 } 1629 } 1630 } 1631 { 1632 LOCK(m_tx_download_mutex); 1633 m_txdownloadman.DisconnectedPeer(nodeid); 1634 } 1635 if (m_txreconciliation) m_txreconciliation->ForgetPeer(nodeid); 1636 m_num_preferred_download_peers -= state->fPreferredDownload; 1637 m_peers_downloading_from -= (!state->vBlocksInFlight.empty()); 1638 assert(m_peers_downloading_from >= 0); 1639 m_outbound_peers_with_protect_from_disconnect -= state->m_chain_sync.m_protect; 1640 assert(m_outbound_peers_with_protect_from_disconnect >= 0); 1641 1642 m_node_states.erase(nodeid); 1643 1644 if (m_node_states.empty()) { 1645 // Do a consistency check after the last peer is removed. 1646 assert(mapBlocksInFlight.empty()); 1647 assert(m_num_preferred_download_peers == 0); 1648 assert(m_peers_downloading_from == 0); 1649 assert(m_outbound_peers_with_protect_from_disconnect == 0); 1650 assert(m_wtxid_relay_peers == 0); 1651 WITH_LOCK(m_tx_download_mutex, m_txdownloadman.CheckIsEmpty()); 1652 } 1653 } // cs_main 1654 if (node.fSuccessfullyConnected && 1655 !node.IsBlockOnlyConn() && !node.IsInboundConn()) { 1656 // Only change visible addrman state for full outbound peers. We don't 1657 // call Connected() for feeler connections since they don't have 1658 // fSuccessfullyConnected set. 1659 m_addrman.Connected(node.addr); 1660 } 1661 { 1662 LOCK(m_headers_presync_mutex); 1663 m_headers_presync_stats.erase(nodeid); 1664 } 1665 LogDebug(BCLog::NET, "Cleared nodestate for peer=%d\n", nodeid); 1666 } 1667 1668 bool PeerManagerImpl::HasAllDesirableServiceFlags(ServiceFlags services) const 1669 { 1670 // Shortcut for (services & GetDesirableServiceFlags(services)) == GetDesirableServiceFlags(services) 1671 return !(GetDesirableServiceFlags(services) & (~services)); 1672 } 1673 1674 ServiceFlags PeerManagerImpl::GetDesirableServiceFlags(ServiceFlags services) const 1675 { 1676 if (services & NODE_NETWORK_LIMITED) { 1677 // Limited peers are desirable when we are close to the tip. 1678 if (ApproximateBestBlockDepth() < NODE_NETWORK_LIMITED_ALLOW_CONN_BLOCKS) { 1679 return ServiceFlags(NODE_NETWORK_LIMITED | NODE_WITNESS); 1680 } 1681 } 1682 return ServiceFlags(NODE_NETWORK | NODE_WITNESS); 1683 } 1684 1685 PeerRef PeerManagerImpl::GetPeerRef(NodeId id) const 1686 { 1687 LOCK(m_peer_mutex); 1688 auto it = m_peer_map.find(id); 1689 return it != m_peer_map.end() ? it->second : nullptr; 1690 } 1691 1692 PeerRef PeerManagerImpl::RemovePeer(NodeId id) 1693 { 1694 PeerRef ret; 1695 LOCK(m_peer_mutex); 1696 auto it = m_peer_map.find(id); 1697 if (it != m_peer_map.end()) { 1698 ret = std::move(it->second); 1699 m_peer_map.erase(it); 1700 } 1701 return ret; 1702 } 1703 1704 bool PeerManagerImpl::GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats) const 1705 { 1706 { 1707 LOCK(cs_main); 1708 const CNodeState* state = State(nodeid); 1709 if (state == nullptr) 1710 return false; 1711 stats.nSyncHeight = state->pindexBestKnownBlock ? state->pindexBestKnownBlock->nHeight : -1; 1712 stats.nCommonHeight = state->pindexLastCommonBlock ? state->pindexLastCommonBlock->nHeight : -1; 1713 for (const QueuedBlock& queue : state->vBlocksInFlight) { 1714 if (queue.pindex) 1715 stats.vHeightInFlight.push_back(queue.pindex->nHeight); 1716 } 1717 } 1718 1719 PeerRef peer = GetPeerRef(nodeid); 1720 if (peer == nullptr) return false; 1721 stats.their_services = peer->m_their_services; 1722 stats.m_starting_height = peer->m_starting_height; 1723 // It is common for nodes with good ping times to suddenly become lagged, 1724 // due to a new block arriving or other large transfer. 1725 // Merely reporting pingtime might fool the caller into thinking the node was still responsive, 1726 // since pingtime does not update until the ping is complete, which might take a while. 1727 // So, if a ping is taking an unusually long time in flight, 1728 // the caller can immediately detect that this is happening. 1729 auto ping_wait{0us}; 1730 if ((0 != peer->m_ping_nonce_sent) && (0 != peer->m_ping_start.load().count())) { 1731 ping_wait = GetTime<std::chrono::microseconds>() - peer->m_ping_start.load(); 1732 } 1733 1734 if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 1735 stats.m_relay_txs = WITH_LOCK(tx_relay->m_bloom_filter_mutex, return tx_relay->m_relay_txs); 1736 stats.m_fee_filter_received = tx_relay->m_fee_filter_received.load(); 1737 } else { 1738 stats.m_relay_txs = false; 1739 stats.m_fee_filter_received = 0; 1740 } 1741 1742 stats.m_ping_wait = ping_wait; 1743 stats.m_addr_processed = peer->m_addr_processed.load(); 1744 stats.m_addr_rate_limited = peer->m_addr_rate_limited.load(); 1745 stats.m_addr_relay_enabled = peer->m_addr_relay_enabled.load(); 1746 { 1747 LOCK(peer->m_headers_sync_mutex); 1748 if (peer->m_headers_sync) { 1749 stats.presync_height = peer->m_headers_sync->GetPresyncHeight(); 1750 } 1751 } 1752 stats.time_offset = peer->m_time_offset; 1753 1754 return true; 1755 } 1756 1757 std::vector<TxOrphanage::OrphanTxBase> PeerManagerImpl::GetOrphanTransactions() 1758 { 1759 LOCK(m_tx_download_mutex); 1760 return m_txdownloadman.GetOrphanTransactions(); 1761 } 1762 1763 PeerManagerInfo PeerManagerImpl::GetInfo() const 1764 { 1765 return PeerManagerInfo{ 1766 .median_outbound_time_offset = m_outbound_time_offsets.Median(), 1767 .ignores_incoming_txs = m_opts.ignore_incoming_txs, 1768 }; 1769 } 1770 1771 void PeerManagerImpl::AddToCompactExtraTransactions(const CTransactionRef& tx) 1772 { 1773 if (m_opts.max_extra_txs <= 0) 1774 return; 1775 if (!vExtraTxnForCompact.size()) 1776 vExtraTxnForCompact.resize(m_opts.max_extra_txs); 1777 vExtraTxnForCompact[vExtraTxnForCompactIt] = tx; 1778 vExtraTxnForCompactIt = (vExtraTxnForCompactIt + 1) % m_opts.max_extra_txs; 1779 } 1780 1781 void PeerManagerImpl::Misbehaving(Peer& peer, const std::string& message) 1782 { 1783 LOCK(peer.m_misbehavior_mutex); 1784 1785 const std::string message_prefixed = message.empty() ? "" : (": " + message); 1786 peer.m_should_discourage = true; 1787 LogDebug(BCLog::NET, "Misbehaving: peer=%d%s\n", peer.m_id, message_prefixed); 1788 TRACEPOINT(net, misbehaving_connection, 1789 peer.m_id, 1790 message.c_str() 1791 ); 1792 } 1793 1794 void PeerManagerImpl::MaybePunishNodeForBlock(NodeId nodeid, const BlockValidationState& state, 1795 bool via_compact_block, const std::string& message) 1796 { 1797 PeerRef peer{GetPeerRef(nodeid)}; 1798 switch (state.GetResult()) { 1799 case BlockValidationResult::BLOCK_RESULT_UNSET: 1800 break; 1801 case BlockValidationResult::BLOCK_HEADER_LOW_WORK: 1802 // We didn't try to process the block because the header chain may have 1803 // too little work. 1804 break; 1805 // The node is providing invalid data: 1806 case BlockValidationResult::BLOCK_CONSENSUS: 1807 case BlockValidationResult::BLOCK_MUTATED: 1808 if (!via_compact_block) { 1809 if (peer) Misbehaving(*peer, message); 1810 return; 1811 } 1812 break; 1813 case BlockValidationResult::BLOCK_CACHED_INVALID: 1814 { 1815 // Discourage outbound (but not inbound) peers if on an invalid chain. 1816 // Exempt HB compact block peers. Manual connections are always protected from discouragement. 1817 if (peer && !via_compact_block && !peer->m_is_inbound) { 1818 if (peer) Misbehaving(*peer, message); 1819 return; 1820 } 1821 break; 1822 } 1823 case BlockValidationResult::BLOCK_INVALID_HEADER: 1824 case BlockValidationResult::BLOCK_INVALID_PREV: 1825 if (peer) Misbehaving(*peer, message); 1826 return; 1827 // Conflicting (but not necessarily invalid) data or different policy: 1828 case BlockValidationResult::BLOCK_MISSING_PREV: 1829 if (peer) Misbehaving(*peer, message); 1830 return; 1831 case BlockValidationResult::BLOCK_TIME_FUTURE: 1832 break; 1833 } 1834 if (message != "") { 1835 LogDebug(BCLog::NET, "peer=%d: %s\n", nodeid, message); 1836 } 1837 } 1838 1839 void PeerManagerImpl::MaybePunishNodeForTx(NodeId nodeid, const TxValidationState& state) 1840 { 1841 PeerRef peer{GetPeerRef(nodeid)}; 1842 switch (state.GetResult()) { 1843 case TxValidationResult::TX_RESULT_UNSET: 1844 break; 1845 // The node is providing invalid data: 1846 case TxValidationResult::TX_CONSENSUS: 1847 if (peer) Misbehaving(*peer, ""); 1848 return; 1849 // Conflicting (but not necessarily invalid) data or different policy: 1850 case TxValidationResult::TX_INPUTS_NOT_STANDARD: 1851 case TxValidationResult::TX_NOT_STANDARD: 1852 case TxValidationResult::TX_MISSING_INPUTS: 1853 case TxValidationResult::TX_PREMATURE_SPEND: 1854 case TxValidationResult::TX_WITNESS_MUTATED: 1855 case TxValidationResult::TX_WITNESS_STRIPPED: 1856 case TxValidationResult::TX_CONFLICT: 1857 case TxValidationResult::TX_MEMPOOL_POLICY: 1858 case TxValidationResult::TX_NO_MEMPOOL: 1859 case TxValidationResult::TX_RECONSIDERABLE: 1860 case TxValidationResult::TX_UNKNOWN: 1861 break; 1862 } 1863 } 1864 1865 bool PeerManagerImpl::BlockRequestAllowed(const CBlockIndex* pindex) 1866 { 1867 AssertLockHeld(cs_main); 1868 if (m_chainman.ActiveChain().Contains(pindex)) return true; 1869 return pindex->IsValid(BLOCK_VALID_SCRIPTS) && (m_chainman.m_best_header != nullptr) && 1870 (m_chainman.m_best_header->GetBlockTime() - pindex->GetBlockTime() < STALE_RELAY_AGE_LIMIT) && 1871 (GetBlockProofEquivalentTime(*m_chainman.m_best_header, *pindex, *m_chainman.m_best_header, m_chainparams.GetConsensus()) < STALE_RELAY_AGE_LIMIT); 1872 } 1873 1874 std::optional<std::string> PeerManagerImpl::FetchBlock(NodeId peer_id, const CBlockIndex& block_index) 1875 { 1876 if (m_chainman.m_blockman.LoadingBlocks()) return "Loading blocks ..."; 1877 1878 // Ensure this peer exists and hasn't been disconnected 1879 PeerRef peer = GetPeerRef(peer_id); 1880 if (peer == nullptr) return "Peer does not exist"; 1881 1882 // Ignore pre-segwit peers 1883 if (!CanServeWitnesses(*peer)) return "Pre-SegWit peer"; 1884 1885 LOCK(cs_main); 1886 1887 // Forget about all prior requests 1888 RemoveBlockRequest(block_index.GetBlockHash(), std::nullopt); 1889 1890 // Mark block as in-flight 1891 if (!BlockRequested(peer_id, block_index)) return "Already requested from this peer"; 1892 1893 // Construct message to request the block 1894 const uint256& hash{block_index.GetBlockHash()}; 1895 std::vector<CInv> invs{CInv(MSG_BLOCK | MSG_WITNESS_FLAG, hash)}; 1896 1897 // Send block request message to the peer 1898 bool success = m_connman.ForNode(peer_id, [this, &invs](CNode* node) { 1899 this->MakeAndPushMessage(*node, NetMsgType::GETDATA, invs); 1900 return true; 1901 }); 1902 1903 if (!success) return "Peer not fully connected"; 1904 1905 LogDebug(BCLog::NET, "Requesting block %s from peer=%d\n", 1906 hash.ToString(), peer_id); 1907 return std::nullopt; 1908 } 1909 1910 std::unique_ptr<PeerManager> PeerManager::make(CConnman& connman, AddrMan& addrman, 1911 BanMan* banman, ChainstateManager& chainman, 1912 CTxMemPool& pool, node::Warnings& warnings, Options opts) 1913 { 1914 return std::make_unique<PeerManagerImpl>(connman, addrman, banman, chainman, pool, warnings, opts); 1915 } 1916 1917 PeerManagerImpl::PeerManagerImpl(CConnman& connman, AddrMan& addrman, 1918 BanMan* banman, ChainstateManager& chainman, 1919 CTxMemPool& pool, node::Warnings& warnings, Options opts) 1920 : m_rng{opts.deterministic_rng}, 1921 m_fee_filter_rounder{CFeeRate{DEFAULT_MIN_RELAY_TX_FEE}, m_rng}, 1922 m_chainparams(chainman.GetParams()), 1923 m_connman(connman), 1924 m_addrman(addrman), 1925 m_banman(banman), 1926 m_chainman(chainman), 1927 m_mempool(pool), 1928 m_txdownloadman(node::TxDownloadOptions{pool, m_rng, opts.max_orphan_txs, opts.deterministic_rng}), 1929 m_warnings{warnings}, 1930 m_opts{opts} 1931 { 1932 // While Erlay support is incomplete, it must be enabled explicitly via -txreconciliation. 1933 // This argument can go away after Erlay support is complete. 1934 if (opts.reconcile_txs) { 1935 m_txreconciliation = std::make_unique<TxReconciliationTracker>(TXRECONCILIATION_VERSION); 1936 } 1937 } 1938 1939 void PeerManagerImpl::StartScheduledTasks(CScheduler& scheduler) 1940 { 1941 // Stale tip checking and peer eviction are on two different timers, but we 1942 // don't want them to get out of sync due to drift in the scheduler, so we 1943 // combine them in one function and schedule at the quicker (peer-eviction) 1944 // timer. 1945 static_assert(EXTRA_PEER_CHECK_INTERVAL < STALE_CHECK_INTERVAL, "peer eviction timer should be less than stale tip check timer"); 1946 scheduler.scheduleEvery([this] { this->CheckForStaleTipAndEvictPeers(); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL}); 1947 1948 // schedule next run for 10-15 minutes in the future 1949 const auto delta = 10min + FastRandomContext().randrange<std::chrono::milliseconds>(5min); 1950 scheduler.scheduleFromNow([&] { ReattemptInitialBroadcast(scheduler); }, delta); 1951 } 1952 1953 void PeerManagerImpl::ActiveTipChange(const CBlockIndex& new_tip, bool is_ibd) 1954 { 1955 // Ensure mempool mutex was released, otherwise deadlock may occur if another thread holding 1956 // m_tx_download_mutex waits on the mempool mutex. 1957 AssertLockNotHeld(m_mempool.cs); 1958 AssertLockNotHeld(m_tx_download_mutex); 1959 1960 if (!is_ibd) { 1961 LOCK(m_tx_download_mutex); 1962 // If the chain tip has changed, previously rejected transactions might now be valid, e.g. due 1963 // to a timelock. Reset the rejection filters to give those transactions another chance if we 1964 // see them again. 1965 m_txdownloadman.ActiveTipChange(); 1966 } 1967 } 1968 1969 /** 1970 * Evict orphan txn pool entries based on a newly connected 1971 * block, remember the recently confirmed transactions, and delete tracked 1972 * announcements for them. Also save the time of the last tip update and 1973 * possibly reduce dynamic block stalling timeout. 1974 */ 1975 void PeerManagerImpl::BlockConnected( 1976 ChainstateRole role, 1977 const std::shared_ptr<const CBlock>& pblock, 1978 const CBlockIndex* pindex) 1979 { 1980 // Update this for all chainstate roles so that we don't mistakenly see peers 1981 // helping us do background IBD as having a stale tip. 1982 m_last_tip_update = GetTime<std::chrono::seconds>(); 1983 1984 // In case the dynamic timeout was doubled once or more, reduce it slowly back to its default value 1985 auto stalling_timeout = m_block_stalling_timeout.load(); 1986 Assume(stalling_timeout >= BLOCK_STALLING_TIMEOUT_DEFAULT); 1987 if (stalling_timeout != BLOCK_STALLING_TIMEOUT_DEFAULT) { 1988 const auto new_timeout = std::max(std::chrono::duration_cast<std::chrono::seconds>(stalling_timeout * 0.85), BLOCK_STALLING_TIMEOUT_DEFAULT); 1989 if (m_block_stalling_timeout.compare_exchange_strong(stalling_timeout, new_timeout)) { 1990 LogDebug(BCLog::NET, "Decreased stalling timeout to %d seconds\n", count_seconds(new_timeout)); 1991 } 1992 } 1993 1994 // The following task can be skipped since we don't maintain a mempool for 1995 // the ibd/background chainstate. 1996 if (role == ChainstateRole::BACKGROUND) { 1997 return; 1998 } 1999 LOCK(m_tx_download_mutex); 2000 m_txdownloadman.BlockConnected(pblock); 2001 } 2002 2003 void PeerManagerImpl::BlockDisconnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex* pindex) 2004 { 2005 LOCK(m_tx_download_mutex); 2006 m_txdownloadman.BlockDisconnected(); 2007 } 2008 2009 /** 2010 * Maintain state about the best-seen block and fast-announce a compact block 2011 * to compatible peers. 2012 */ 2013 void PeerManagerImpl::NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& pblock) 2014 { 2015 auto pcmpctblock = std::make_shared<const CBlockHeaderAndShortTxIDs>(*pblock, FastRandomContext().rand64()); 2016 2017 LOCK(cs_main); 2018 2019 if (pindex->nHeight <= m_highest_fast_announce) 2020 return; 2021 m_highest_fast_announce = pindex->nHeight; 2022 2023 if (!DeploymentActiveAt(*pindex, m_chainman, Consensus::DEPLOYMENT_SEGWIT)) return; 2024 2025 uint256 hashBlock(pblock->GetHash()); 2026 const std::shared_future<CSerializedNetMsg> lazy_ser{ 2027 std::async(std::launch::deferred, [&] { return NetMsg::Make(NetMsgType::CMPCTBLOCK, *pcmpctblock); })}; 2028 2029 { 2030 auto most_recent_block_txs = std::make_unique<std::map<uint256, CTransactionRef>>(); 2031 for (const auto& tx : pblock->vtx) { 2032 most_recent_block_txs->emplace(tx->GetHash(), tx); 2033 most_recent_block_txs->emplace(tx->GetWitnessHash(), tx); 2034 } 2035 2036 LOCK(m_most_recent_block_mutex); 2037 m_most_recent_block_hash = hashBlock; 2038 m_most_recent_block = pblock; 2039 m_most_recent_compact_block = pcmpctblock; 2040 m_most_recent_block_txs = std::move(most_recent_block_txs); 2041 } 2042 2043 m_connman.ForEachNode([this, pindex, &lazy_ser, &hashBlock](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) { 2044 AssertLockHeld(::cs_main); 2045 2046 if (pnode->GetCommonVersion() < INVALID_CB_NO_BAN_VERSION || pnode->fDisconnect) 2047 return; 2048 ProcessBlockAvailability(pnode->GetId()); 2049 CNodeState &state = *State(pnode->GetId()); 2050 // If the peer has, or we announced to them the previous block already, 2051 // but we don't think they have this one, go ahead and announce it 2052 if (state.m_requested_hb_cmpctblocks && !PeerHasHeader(&state, pindex) && PeerHasHeader(&state, pindex->pprev)) { 2053 2054 LogDebug(BCLog::NET, "%s sending header-and-ids %s to peer=%d\n", "PeerManager::NewPoWValidBlock", 2055 hashBlock.ToString(), pnode->GetId()); 2056 2057 const CSerializedNetMsg& ser_cmpctblock{lazy_ser.get()}; 2058 PushMessage(*pnode, ser_cmpctblock.Copy()); 2059 state.pindexBestHeaderSent = pindex; 2060 } 2061 }); 2062 } 2063 2064 /** 2065 * Update our best height and announce any block hashes which weren't previously 2066 * in m_chainman.ActiveChain() to our peers. 2067 */ 2068 void PeerManagerImpl::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) 2069 { 2070 SetBestBlock(pindexNew->nHeight, std::chrono::seconds{pindexNew->GetBlockTime()}); 2071 2072 // Don't relay inventory during initial block download. 2073 if (fInitialDownload) return; 2074 2075 // Find the hashes of all blocks that weren't previously in the best chain. 2076 std::vector<uint256> vHashes; 2077 const CBlockIndex *pindexToAnnounce = pindexNew; 2078 while (pindexToAnnounce != pindexFork) { 2079 vHashes.push_back(pindexToAnnounce->GetBlockHash()); 2080 pindexToAnnounce = pindexToAnnounce->pprev; 2081 if (vHashes.size() == MAX_BLOCKS_TO_ANNOUNCE) { 2082 // Limit announcements in case of a huge reorganization. 2083 // Rely on the peer's synchronization mechanism in that case. 2084 break; 2085 } 2086 } 2087 2088 { 2089 LOCK(m_peer_mutex); 2090 for (auto& it : m_peer_map) { 2091 Peer& peer = *it.second; 2092 LOCK(peer.m_block_inv_mutex); 2093 for (const uint256& hash : vHashes | std::views::reverse) { 2094 peer.m_blocks_for_headers_relay.push_back(hash); 2095 } 2096 } 2097 } 2098 2099 m_connman.WakeMessageHandler(); 2100 } 2101 2102 /** 2103 * Handle invalid block rejection and consequent peer discouragement, maintain which 2104 * peers announce compact blocks. 2105 */ 2106 void PeerManagerImpl::BlockChecked(const CBlock& block, const BlockValidationState& state) 2107 { 2108 LOCK(cs_main); 2109 2110 const uint256 hash(block.GetHash()); 2111 std::map<uint256, std::pair<NodeId, bool>>::iterator it = mapBlockSource.find(hash); 2112 2113 // If the block failed validation, we know where it came from and we're still connected 2114 // to that peer, maybe punish. 2115 if (state.IsInvalid() && 2116 it != mapBlockSource.end() && 2117 State(it->second.first)) { 2118 MaybePunishNodeForBlock(/*nodeid=*/ it->second.first, state, /*via_compact_block=*/ !it->second.second); 2119 } 2120 // Check that: 2121 // 1. The block is valid 2122 // 2. We're not in initial block download 2123 // 3. This is currently the best block we're aware of. We haven't updated 2124 // the tip yet so we have no way to check this directly here. Instead we 2125 // just check that there are currently no other blocks in flight. 2126 else if (state.IsValid() && 2127 !m_chainman.IsInitialBlockDownload() && 2128 mapBlocksInFlight.count(hash) == mapBlocksInFlight.size()) { 2129 if (it != mapBlockSource.end()) { 2130 MaybeSetPeerAsAnnouncingHeaderAndIDs(it->second.first); 2131 } 2132 } 2133 if (it != mapBlockSource.end()) 2134 mapBlockSource.erase(it); 2135 } 2136 2137 ////////////////////////////////////////////////////////////////////////////// 2138 // 2139 // Messages 2140 // 2141 2142 bool PeerManagerImpl::AlreadyHaveBlock(const uint256& block_hash) 2143 { 2144 return m_chainman.m_blockman.LookupBlockIndex(block_hash) != nullptr; 2145 } 2146 2147 void PeerManagerImpl::SendPings() 2148 { 2149 LOCK(m_peer_mutex); 2150 for(auto& it : m_peer_map) it.second->m_ping_queued = true; 2151 } 2152 2153 void PeerManagerImpl::RelayTransaction(const uint256& txid, const uint256& wtxid) 2154 { 2155 LOCK(m_peer_mutex); 2156 for(auto& it : m_peer_map) { 2157 Peer& peer = *it.second; 2158 auto tx_relay = peer.GetTxRelay(); 2159 if (!tx_relay) continue; 2160 2161 LOCK(tx_relay->m_tx_inventory_mutex); 2162 // Only queue transactions for announcement once the version handshake 2163 // is completed. The time of arrival for these transactions is 2164 // otherwise at risk of leaking to a spy, if the spy is able to 2165 // distinguish transactions received during the handshake from the rest 2166 // in the announcement. 2167 if (tx_relay->m_next_inv_send_time == 0s) continue; 2168 2169 const uint256& hash{peer.m_wtxid_relay ? wtxid : txid}; 2170 if (!tx_relay->m_tx_inventory_known_filter.contains(hash)) { 2171 tx_relay->m_tx_inventory_to_send.insert(hash); 2172 } 2173 }; 2174 } 2175 2176 void PeerManagerImpl::RelayAddress(NodeId originator, 2177 const CAddress& addr, 2178 bool fReachable) 2179 { 2180 // We choose the same nodes within a given 24h window (if the list of connected 2181 // nodes does not change) and we don't relay to nodes that already know an 2182 // address. So within 24h we will likely relay a given address once. This is to 2183 // prevent a peer from unjustly giving their address better propagation by sending 2184 // it to us repeatedly. 2185 2186 if (!fReachable && !addr.IsRelayable()) return; 2187 2188 // Relay to a limited number of other nodes 2189 // Use deterministic randomness to send to the same nodes for 24 hours 2190 // at a time so the m_addr_knowns of the chosen nodes prevent repeats 2191 const uint64_t hash_addr{CServiceHash(0, 0)(addr)}; 2192 const auto current_time{GetTime<std::chrono::seconds>()}; 2193 // Adding address hash makes exact rotation time different per address, while preserving periodicity. 2194 const uint64_t time_addr{(static_cast<uint64_t>(count_seconds(current_time)) + hash_addr) / count_seconds(ROTATE_ADDR_RELAY_DEST_INTERVAL)}; 2195 const CSipHasher hasher{m_connman.GetDeterministicRandomizer(RANDOMIZER_ID_ADDRESS_RELAY) 2196 .Write(hash_addr) 2197 .Write(time_addr)}; 2198 2199 // Relay reachable addresses to 2 peers. Unreachable addresses are relayed randomly to 1 or 2 peers. 2200 unsigned int nRelayNodes = (fReachable || (hasher.Finalize() & 1)) ? 2 : 1; 2201 2202 std::array<std::pair<uint64_t, Peer*>, 2> best{{{0, nullptr}, {0, nullptr}}}; 2203 assert(nRelayNodes <= best.size()); 2204 2205 LOCK(m_peer_mutex); 2206 2207 for (auto& [id, peer] : m_peer_map) { 2208 if (peer->m_addr_relay_enabled && id != originator && IsAddrCompatible(*peer, addr)) { 2209 uint64_t hashKey = CSipHasher(hasher).Write(id).Finalize(); 2210 for (unsigned int i = 0; i < nRelayNodes; i++) { 2211 if (hashKey > best[i].first) { 2212 std::copy(best.begin() + i, best.begin() + nRelayNodes - 1, best.begin() + i + 1); 2213 best[i] = std::make_pair(hashKey, peer.get()); 2214 break; 2215 } 2216 } 2217 } 2218 }; 2219 2220 for (unsigned int i = 0; i < nRelayNodes && best[i].first != 0; i++) { 2221 PushAddress(*best[i].second, addr); 2222 } 2223 } 2224 2225 void PeerManagerImpl::ProcessGetBlockData(CNode& pfrom, Peer& peer, const CInv& inv) 2226 { 2227 std::shared_ptr<const CBlock> a_recent_block; 2228 std::shared_ptr<const CBlockHeaderAndShortTxIDs> a_recent_compact_block; 2229 { 2230 LOCK(m_most_recent_block_mutex); 2231 a_recent_block = m_most_recent_block; 2232 a_recent_compact_block = m_most_recent_compact_block; 2233 } 2234 2235 bool need_activate_chain = false; 2236 { 2237 LOCK(cs_main); 2238 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(inv.hash); 2239 if (pindex) { 2240 if (pindex->HaveNumChainTxs() && !pindex->IsValid(BLOCK_VALID_SCRIPTS) && 2241 pindex->IsValid(BLOCK_VALID_TREE)) { 2242 // If we have the block and all of its parents, but have not yet validated it, 2243 // we might be in the middle of connecting it (ie in the unlock of cs_main 2244 // before ActivateBestChain but after AcceptBlock). 2245 // In this case, we need to run ActivateBestChain prior to checking the relay 2246 // conditions below. 2247 need_activate_chain = true; 2248 } 2249 } 2250 } // release cs_main before calling ActivateBestChain 2251 if (need_activate_chain) { 2252 BlockValidationState state; 2253 if (!m_chainman.ActiveChainstate().ActivateBestChain(state, a_recent_block)) { 2254 LogDebug(BCLog::NET, "failed to activate chain (%s)\n", state.ToString()); 2255 } 2256 } 2257 2258 const CBlockIndex* pindex{nullptr}; 2259 const CBlockIndex* tip{nullptr}; 2260 bool can_direct_fetch{false}; 2261 FlatFilePos block_pos{}; 2262 { 2263 LOCK(cs_main); 2264 pindex = m_chainman.m_blockman.LookupBlockIndex(inv.hash); 2265 if (!pindex) { 2266 return; 2267 } 2268 if (!BlockRequestAllowed(pindex)) { 2269 LogDebug(BCLog::NET, "%s: ignoring request from peer=%i for old block that isn't in the main chain\n", __func__, pfrom.GetId()); 2270 return; 2271 } 2272 // disconnect node in case we have reached the outbound limit for serving historical blocks 2273 if (m_connman.OutboundTargetReached(true) && 2274 (((m_chainman.m_best_header != nullptr) && (m_chainman.m_best_header->GetBlockTime() - pindex->GetBlockTime() > HISTORICAL_BLOCK_AGE)) || inv.IsMsgFilteredBlk()) && 2275 !pfrom.HasPermission(NetPermissionFlags::Download) // nodes with the download permission may exceed target 2276 ) { 2277 LogDebug(BCLog::NET, "historical block serving limit reached, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2278 pfrom.fDisconnect = true; 2279 return; 2280 } 2281 tip = m_chainman.ActiveChain().Tip(); 2282 // Avoid leaking prune-height by never sending blocks below the NODE_NETWORK_LIMITED threshold 2283 if (!pfrom.HasPermission(NetPermissionFlags::NoBan) && ( 2284 (((peer.m_our_services & NODE_NETWORK_LIMITED) == NODE_NETWORK_LIMITED) && ((peer.m_our_services & NODE_NETWORK) != NODE_NETWORK) && (tip->nHeight - pindex->nHeight > (int)NODE_NETWORK_LIMITED_MIN_BLOCKS + 2 /* add two blocks buffer extension for possible races */) ) 2285 )) { 2286 LogDebug(BCLog::NET, "Ignore block request below NODE_NETWORK_LIMITED threshold, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2287 //disconnect node and prevent it from stalling (would otherwise wait for the missing block) 2288 pfrom.fDisconnect = true; 2289 return; 2290 } 2291 // Pruned nodes may have deleted the block, so check whether 2292 // it's available before trying to send. 2293 if (!(pindex->nStatus & BLOCK_HAVE_DATA)) { 2294 return; 2295 } 2296 can_direct_fetch = CanDirectFetch(); 2297 block_pos = pindex->GetBlockPos(); 2298 } 2299 2300 std::shared_ptr<const CBlock> pblock; 2301 if (a_recent_block && a_recent_block->GetHash() == pindex->GetBlockHash()) { 2302 pblock = a_recent_block; 2303 } else if (inv.IsMsgWitnessBlk()) { 2304 // Fast-path: in this case it is possible to serve the block directly from disk, 2305 // as the network format matches the format on disk 2306 std::vector<uint8_t> block_data; 2307 if (!m_chainman.m_blockman.ReadRawBlock(block_data, block_pos)) { 2308 if (WITH_LOCK(m_chainman.GetMutex(), return m_chainman.m_blockman.IsBlockPruned(*pindex))) { 2309 LogDebug(BCLog::NET, "Block was pruned before it could be read, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2310 } else { 2311 LogError("Cannot load block from disk, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2312 } 2313 pfrom.fDisconnect = true; 2314 return; 2315 } 2316 MakeAndPushMessage(pfrom, NetMsgType::BLOCK, std::span{block_data}); 2317 // Don't set pblock as we've sent the block 2318 } else { 2319 // Send block from disk 2320 std::shared_ptr<CBlock> pblockRead = std::make_shared<CBlock>(); 2321 if (!m_chainman.m_blockman.ReadBlock(*pblockRead, block_pos)) { 2322 if (WITH_LOCK(m_chainman.GetMutex(), return m_chainman.m_blockman.IsBlockPruned(*pindex))) { 2323 LogDebug(BCLog::NET, "Block was pruned before it could be read, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2324 } else { 2325 LogError("Cannot load block from disk, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2326 } 2327 pfrom.fDisconnect = true; 2328 return; 2329 } 2330 pblock = pblockRead; 2331 } 2332 if (pblock) { 2333 if (inv.IsMsgBlk()) { 2334 MakeAndPushMessage(pfrom, NetMsgType::BLOCK, TX_NO_WITNESS(*pblock)); 2335 } else if (inv.IsMsgWitnessBlk()) { 2336 MakeAndPushMessage(pfrom, NetMsgType::BLOCK, TX_WITH_WITNESS(*pblock)); 2337 } else if (inv.IsMsgFilteredBlk()) { 2338 bool sendMerkleBlock = false; 2339 CMerkleBlock merkleBlock; 2340 if (auto tx_relay = peer.GetTxRelay(); tx_relay != nullptr) { 2341 LOCK(tx_relay->m_bloom_filter_mutex); 2342 if (tx_relay->m_bloom_filter) { 2343 sendMerkleBlock = true; 2344 merkleBlock = CMerkleBlock(*pblock, *tx_relay->m_bloom_filter); 2345 } 2346 } 2347 if (sendMerkleBlock) { 2348 MakeAndPushMessage(pfrom, NetMsgType::MERKLEBLOCK, merkleBlock); 2349 // CMerkleBlock just contains hashes, so also push any transactions in the block the client did not see 2350 // This avoids hurting performance by pointlessly requiring a round-trip 2351 // Note that there is currently no way for a node to request any single transactions we didn't send here - 2352 // they must either disconnect and retry or request the full block. 2353 // Thus, the protocol spec specified allows for us to provide duplicate txn here, 2354 // however we MUST always provide at least what the remote peer needs 2355 typedef std::pair<unsigned int, uint256> PairType; 2356 for (PairType& pair : merkleBlock.vMatchedTxn) 2357 MakeAndPushMessage(pfrom, NetMsgType::TX, TX_NO_WITNESS(*pblock->vtx[pair.first])); 2358 } 2359 // else 2360 // no response 2361 } else if (inv.IsMsgCmpctBlk()) { 2362 // If a peer is asking for old blocks, we're almost guaranteed 2363 // they won't have a useful mempool to match against a compact block, 2364 // and we don't feel like constructing the object for them, so 2365 // instead we respond with the full, non-compact block. 2366 if (can_direct_fetch && pindex->nHeight >= tip->nHeight - MAX_CMPCTBLOCK_DEPTH) { 2367 if (a_recent_compact_block && a_recent_compact_block->header.GetHash() == pindex->GetBlockHash()) { 2368 MakeAndPushMessage(pfrom, NetMsgType::CMPCTBLOCK, *a_recent_compact_block); 2369 } else { 2370 CBlockHeaderAndShortTxIDs cmpctblock{*pblock, m_rng.rand64()}; 2371 MakeAndPushMessage(pfrom, NetMsgType::CMPCTBLOCK, cmpctblock); 2372 } 2373 } else { 2374 MakeAndPushMessage(pfrom, NetMsgType::BLOCK, TX_WITH_WITNESS(*pblock)); 2375 } 2376 } 2377 } 2378 2379 { 2380 LOCK(peer.m_block_inv_mutex); 2381 // Trigger the peer node to send a getblocks request for the next batch of inventory 2382 if (inv.hash == peer.m_continuation_block) { 2383 // Send immediately. This must send even if redundant, 2384 // and we want it right after the last block so they don't 2385 // wait for other stuff first. 2386 std::vector<CInv> vInv; 2387 vInv.emplace_back(MSG_BLOCK, tip->GetBlockHash()); 2388 MakeAndPushMessage(pfrom, NetMsgType::INV, vInv); 2389 peer.m_continuation_block.SetNull(); 2390 } 2391 } 2392 } 2393 2394 CTransactionRef PeerManagerImpl::FindTxForGetData(const Peer::TxRelay& tx_relay, const GenTxid& gtxid) 2395 { 2396 // If a tx was in the mempool prior to the last INV for this peer, permit the request. 2397 auto txinfo = m_mempool.info_for_relay(gtxid, tx_relay.m_last_inv_sequence); 2398 if (txinfo.tx) { 2399 return std::move(txinfo.tx); 2400 } 2401 2402 // Or it might be from the most recent block 2403 { 2404 LOCK(m_most_recent_block_mutex); 2405 if (m_most_recent_block_txs != nullptr) { 2406 auto it = m_most_recent_block_txs->find(gtxid.GetHash()); 2407 if (it != m_most_recent_block_txs->end()) return it->second; 2408 } 2409 } 2410 2411 return {}; 2412 } 2413 2414 void PeerManagerImpl::ProcessGetData(CNode& pfrom, Peer& peer, const std::atomic<bool>& interruptMsgProc) 2415 { 2416 AssertLockNotHeld(cs_main); 2417 2418 auto tx_relay = peer.GetTxRelay(); 2419 2420 std::deque<CInv>::iterator it = peer.m_getdata_requests.begin(); 2421 std::vector<CInv> vNotFound; 2422 2423 // Process as many TX items from the front of the getdata queue as 2424 // possible, since they're common and it's efficient to batch process 2425 // them. 2426 while (it != peer.m_getdata_requests.end() && it->IsGenTxMsg()) { 2427 if (interruptMsgProc) return; 2428 // The send buffer provides backpressure. If there's no space in 2429 // the buffer, pause processing until the next call. 2430 if (pfrom.fPauseSend) break; 2431 2432 const CInv &inv = *it++; 2433 2434 if (tx_relay == nullptr) { 2435 // Ignore GETDATA requests for transactions from block-relay-only 2436 // peers and peers that asked us not to announce transactions. 2437 continue; 2438 } 2439 2440 CTransactionRef tx = FindTxForGetData(*tx_relay, ToGenTxid(inv)); 2441 if (tx) { 2442 // WTX and WITNESS_TX imply we serialize with witness 2443 const auto maybe_with_witness = (inv.IsMsgTx() ? TX_NO_WITNESS : TX_WITH_WITNESS); 2444 MakeAndPushMessage(pfrom, NetMsgType::TX, maybe_with_witness(*tx)); 2445 m_mempool.RemoveUnbroadcastTx(tx->GetHash()); 2446 } else { 2447 vNotFound.push_back(inv); 2448 } 2449 } 2450 2451 // Only process one BLOCK item per call, since they're uncommon and can be 2452 // expensive to process. 2453 if (it != peer.m_getdata_requests.end() && !pfrom.fPauseSend) { 2454 const CInv &inv = *it++; 2455 if (inv.IsGenBlkMsg()) { 2456 ProcessGetBlockData(pfrom, peer, inv); 2457 } 2458 // else: If the first item on the queue is an unknown type, we erase it 2459 // and continue processing the queue on the next call. 2460 // NOTE: previously we wouldn't do so and the peer sending us a malformed GETDATA could 2461 // result in never making progress and this thread using 100% allocated CPU. See 2462 // https://bitcoincore.org/en/2024/07/03/disclose-getdata-cpu. 2463 } 2464 2465 peer.m_getdata_requests.erase(peer.m_getdata_requests.begin(), it); 2466 2467 if (!vNotFound.empty()) { 2468 // Let the peer know that we didn't find what it asked for, so it doesn't 2469 // have to wait around forever. 2470 // SPV clients care about this message: it's needed when they are 2471 // recursively walking the dependencies of relevant unconfirmed 2472 // transactions. SPV clients want to do that because they want to know 2473 // about (and store and rebroadcast and risk analyze) the dependencies 2474 // of transactions relevant to them, without having to download the 2475 // entire memory pool. 2476 // Also, other nodes can use these messages to automatically request a 2477 // transaction from some other peer that announced it, and stop 2478 // waiting for us to respond. 2479 // In normal operation, we often send NOTFOUND messages for parents of 2480 // transactions that we relay; if a peer is missing a parent, they may 2481 // assume we have them and request the parents from us. 2482 MakeAndPushMessage(pfrom, NetMsgType::NOTFOUND, vNotFound); 2483 } 2484 } 2485 2486 uint32_t PeerManagerImpl::GetFetchFlags(const Peer& peer) const 2487 { 2488 uint32_t nFetchFlags = 0; 2489 if (CanServeWitnesses(peer)) { 2490 nFetchFlags |= MSG_WITNESS_FLAG; 2491 } 2492 return nFetchFlags; 2493 } 2494 2495 void PeerManagerImpl::SendBlockTransactions(CNode& pfrom, Peer& peer, const CBlock& block, const BlockTransactionsRequest& req) 2496 { 2497 BlockTransactions resp(req); 2498 for (size_t i = 0; i < req.indexes.size(); i++) { 2499 if (req.indexes[i] >= block.vtx.size()) { 2500 Misbehaving(peer, "getblocktxn with out-of-bounds tx indices"); 2501 return; 2502 } 2503 resp.txn[i] = block.vtx[req.indexes[i]]; 2504 } 2505 2506 MakeAndPushMessage(pfrom, NetMsgType::BLOCKTXN, resp); 2507 } 2508 2509 bool PeerManagerImpl::CheckHeadersPoW(const std::vector<CBlockHeader>& headers, const Consensus::Params& consensusParams, Peer& peer) 2510 { 2511 // Do these headers have proof-of-work matching what's claimed? 2512 if (!HasValidProofOfWork(headers, consensusParams)) { 2513 Misbehaving(peer, "header with invalid proof of work"); 2514 return false; 2515 } 2516 2517 // Are these headers connected to each other? 2518 if (!CheckHeadersAreContinuous(headers)) { 2519 Misbehaving(peer, "non-continuous headers sequence"); 2520 return false; 2521 } 2522 return true; 2523 } 2524 2525 arith_uint256 PeerManagerImpl::GetAntiDoSWorkThreshold() 2526 { 2527 arith_uint256 near_chaintip_work = 0; 2528 LOCK(cs_main); 2529 if (m_chainman.ActiveChain().Tip() != nullptr) { 2530 const CBlockIndex *tip = m_chainman.ActiveChain().Tip(); 2531 // Use a 144 block buffer, so that we'll accept headers that fork from 2532 // near our tip. 2533 near_chaintip_work = tip->nChainWork - std::min<arith_uint256>(144*GetBlockProof(*tip), tip->nChainWork); 2534 } 2535 return std::max(near_chaintip_work, m_chainman.MinimumChainWork()); 2536 } 2537 2538 /** 2539 * Special handling for unconnecting headers that might be part of a block 2540 * announcement. 2541 * 2542 * We'll send a getheaders message in response to try to connect the chain. 2543 */ 2544 void PeerManagerImpl::HandleUnconnectingHeaders(CNode& pfrom, Peer& peer, 2545 const std::vector<CBlockHeader>& headers) 2546 { 2547 // Try to fill in the missing headers. 2548 const CBlockIndex* best_header{WITH_LOCK(cs_main, return m_chainman.m_best_header)}; 2549 if (MaybeSendGetHeaders(pfrom, GetLocator(best_header), peer)) { 2550 LogDebug(BCLog::NET, "received header %s: missing prev block %s, sending getheaders (%d) to end (peer=%d)\n", 2551 headers[0].GetHash().ToString(), 2552 headers[0].hashPrevBlock.ToString(), 2553 best_header->nHeight, 2554 pfrom.GetId()); 2555 } 2556 2557 // Set hashLastUnknownBlock for this peer, so that if we 2558 // eventually get the headers - even from a different peer - 2559 // we can use this peer to download. 2560 WITH_LOCK(cs_main, UpdateBlockAvailability(pfrom.GetId(), headers.back().GetHash())); 2561 } 2562 2563 bool PeerManagerImpl::CheckHeadersAreContinuous(const std::vector<CBlockHeader>& headers) const 2564 { 2565 uint256 hashLastBlock; 2566 for (const CBlockHeader& header : headers) { 2567 if (!hashLastBlock.IsNull() && header.hashPrevBlock != hashLastBlock) { 2568 return false; 2569 } 2570 hashLastBlock = header.GetHash(); 2571 } 2572 return true; 2573 } 2574 2575 bool PeerManagerImpl::IsContinuationOfLowWorkHeadersSync(Peer& peer, CNode& pfrom, std::vector<CBlockHeader>& headers) 2576 { 2577 if (peer.m_headers_sync) { 2578 auto result = peer.m_headers_sync->ProcessNextHeaders(headers, headers.size() == m_opts.max_headers_result); 2579 // If it is a valid continuation, we should treat the existing getheaders request as responded to. 2580 if (result.success) peer.m_last_getheaders_timestamp = {}; 2581 if (result.request_more) { 2582 auto locator = peer.m_headers_sync->NextHeadersRequestLocator(); 2583 // If we were instructed to ask for a locator, it should not be empty. 2584 Assume(!locator.vHave.empty()); 2585 // We can only be instructed to request more if processing was successful. 2586 Assume(result.success); 2587 if (!locator.vHave.empty()) { 2588 // It should be impossible for the getheaders request to fail, 2589 // because we just cleared the last getheaders timestamp. 2590 bool sent_getheaders = MaybeSendGetHeaders(pfrom, locator, peer); 2591 Assume(sent_getheaders); 2592 LogDebug(BCLog::NET, "more getheaders (from %s) to peer=%d\n", 2593 locator.vHave.front().ToString(), pfrom.GetId()); 2594 } 2595 } 2596 2597 if (peer.m_headers_sync->GetState() == HeadersSyncState::State::FINAL) { 2598 peer.m_headers_sync.reset(nullptr); 2599 2600 // Delete this peer's entry in m_headers_presync_stats. 2601 // If this is m_headers_presync_bestpeer, it will be replaced later 2602 // by the next peer that triggers the else{} branch below. 2603 LOCK(m_headers_presync_mutex); 2604 m_headers_presync_stats.erase(pfrom.GetId()); 2605 } else { 2606 // Build statistics for this peer's sync. 2607 HeadersPresyncStats stats; 2608 stats.first = peer.m_headers_sync->GetPresyncWork(); 2609 if (peer.m_headers_sync->GetState() == HeadersSyncState::State::PRESYNC) { 2610 stats.second = {peer.m_headers_sync->GetPresyncHeight(), 2611 peer.m_headers_sync->GetPresyncTime()}; 2612 } 2613 2614 // Update statistics in stats. 2615 LOCK(m_headers_presync_mutex); 2616 m_headers_presync_stats[pfrom.GetId()] = stats; 2617 auto best_it = m_headers_presync_stats.find(m_headers_presync_bestpeer); 2618 bool best_updated = false; 2619 if (best_it == m_headers_presync_stats.end()) { 2620 // If the cached best peer is outdated, iterate over all remaining ones (including 2621 // newly updated one) to find the best one. 2622 NodeId peer_best{-1}; 2623 const HeadersPresyncStats* stat_best{nullptr}; 2624 for (const auto& [peer, stat] : m_headers_presync_stats) { 2625 if (!stat_best || stat > *stat_best) { 2626 peer_best = peer; 2627 stat_best = &stat; 2628 } 2629 } 2630 m_headers_presync_bestpeer = peer_best; 2631 best_updated = (peer_best == pfrom.GetId()); 2632 } else if (best_it->first == pfrom.GetId() || stats > best_it->second) { 2633 // pfrom was and remains the best peer, or pfrom just became best. 2634 m_headers_presync_bestpeer = pfrom.GetId(); 2635 best_updated = true; 2636 } 2637 if (best_updated && stats.second.has_value()) { 2638 // If the best peer updated, and it is in its first phase, signal. 2639 m_headers_presync_should_signal = true; 2640 } 2641 } 2642 2643 if (result.success) { 2644 // We only overwrite the headers passed in if processing was 2645 // successful. 2646 headers.swap(result.pow_validated_headers); 2647 } 2648 2649 return result.success; 2650 } 2651 // Either we didn't have a sync in progress, or something went wrong 2652 // processing these headers, or we are returning headers to the caller to 2653 // process. 2654 return false; 2655 } 2656 2657 bool PeerManagerImpl::TryLowWorkHeadersSync(Peer& peer, CNode& pfrom, const CBlockIndex* chain_start_header, std::vector<CBlockHeader>& headers) 2658 { 2659 // Calculate the claimed total work on this chain. 2660 arith_uint256 total_work = chain_start_header->nChainWork + CalculateClaimedHeadersWork(headers); 2661 2662 // Our dynamic anti-DoS threshold (minimum work required on a headers chain 2663 // before we'll store it) 2664 arith_uint256 minimum_chain_work = GetAntiDoSWorkThreshold(); 2665 2666 // Avoid DoS via low-difficulty-headers by only processing if the headers 2667 // are part of a chain with sufficient work. 2668 if (total_work < minimum_chain_work) { 2669 // Only try to sync with this peer if their headers message was full; 2670 // otherwise they don't have more headers after this so no point in 2671 // trying to sync their too-little-work chain. 2672 if (headers.size() == m_opts.max_headers_result) { 2673 // Note: we could advance to the last header in this set that is 2674 // known to us, rather than starting at the first header (which we 2675 // may already have); however this is unlikely to matter much since 2676 // ProcessHeadersMessage() already handles the case where all 2677 // headers in a received message are already known and are 2678 // ancestors of m_best_header or chainActive.Tip(), by skipping 2679 // this logic in that case. So even if the first header in this set 2680 // of headers is known, some header in this set must be new, so 2681 // advancing to the first unknown header would be a small effect. 2682 LOCK(peer.m_headers_sync_mutex); 2683 peer.m_headers_sync.reset(new HeadersSyncState(peer.m_id, m_chainparams.GetConsensus(), 2684 chain_start_header, minimum_chain_work)); 2685 2686 // Now a HeadersSyncState object for tracking this synchronization 2687 // is created, process the headers using it as normal. Failures are 2688 // handled inside of IsContinuationOfLowWorkHeadersSync. 2689 (void)IsContinuationOfLowWorkHeadersSync(peer, pfrom, headers); 2690 } else { 2691 LogDebug(BCLog::NET, "Ignoring low-work chain (height=%u) from peer=%d\n", chain_start_header->nHeight + headers.size(), pfrom.GetId()); 2692 } 2693 2694 // The peer has not yet given us a chain that meets our work threshold, 2695 // so we want to prevent further processing of the headers in any case. 2696 headers = {}; 2697 return true; 2698 } 2699 2700 return false; 2701 } 2702 2703 bool PeerManagerImpl::IsAncestorOfBestHeaderOrTip(const CBlockIndex* header) 2704 { 2705 if (header == nullptr) { 2706 return false; 2707 } else if (m_chainman.m_best_header != nullptr && header == m_chainman.m_best_header->GetAncestor(header->nHeight)) { 2708 return true; 2709 } else if (m_chainman.ActiveChain().Contains(header)) { 2710 return true; 2711 } 2712 return false; 2713 } 2714 2715 bool PeerManagerImpl::MaybeSendGetHeaders(CNode& pfrom, const CBlockLocator& locator, Peer& peer) 2716 { 2717 const auto current_time = NodeClock::now(); 2718 2719 // Only allow a new getheaders message to go out if we don't have a recent 2720 // one already in-flight 2721 if (current_time - peer.m_last_getheaders_timestamp > HEADERS_RESPONSE_TIME) { 2722 MakeAndPushMessage(pfrom, NetMsgType::GETHEADERS, locator, uint256()); 2723 peer.m_last_getheaders_timestamp = current_time; 2724 return true; 2725 } 2726 return false; 2727 } 2728 2729 /* 2730 * Given a new headers tip ending in last_header, potentially request blocks towards that tip. 2731 * We require that the given tip have at least as much work as our tip, and for 2732 * our current tip to be "close to synced" (see CanDirectFetch()). 2733 */ 2734 void PeerManagerImpl::HeadersDirectFetchBlocks(CNode& pfrom, const Peer& peer, const CBlockIndex& last_header) 2735 { 2736 LOCK(cs_main); 2737 CNodeState *nodestate = State(pfrom.GetId()); 2738 2739 if (CanDirectFetch() && last_header.IsValid(BLOCK_VALID_TREE) && m_chainman.ActiveChain().Tip()->nChainWork <= last_header.nChainWork) { 2740 std::vector<const CBlockIndex*> vToFetch; 2741 const CBlockIndex* pindexWalk{&last_header}; 2742 // Calculate all the blocks we'd need to switch to last_header, up to a limit. 2743 while (pindexWalk && !m_chainman.ActiveChain().Contains(pindexWalk) && vToFetch.size() <= MAX_BLOCKS_IN_TRANSIT_PER_PEER) { 2744 if (!(pindexWalk->nStatus & BLOCK_HAVE_DATA) && 2745 !IsBlockRequested(pindexWalk->GetBlockHash()) && 2746 (!DeploymentActiveAt(*pindexWalk, m_chainman, Consensus::DEPLOYMENT_SEGWIT) || CanServeWitnesses(peer))) { 2747 // We don't have this block, and it's not yet in flight. 2748 vToFetch.push_back(pindexWalk); 2749 } 2750 pindexWalk = pindexWalk->pprev; 2751 } 2752 // If pindexWalk still isn't on our main chain, we're looking at a 2753 // very large reorg at a time we think we're close to caught up to 2754 // the main chain -- this shouldn't really happen. Bail out on the 2755 // direct fetch and rely on parallel download instead. 2756 if (!m_chainman.ActiveChain().Contains(pindexWalk)) { 2757 LogDebug(BCLog::NET, "Large reorg, won't direct fetch to %s (%d)\n", 2758 last_header.GetBlockHash().ToString(), 2759 last_header.nHeight); 2760 } else { 2761 std::vector<CInv> vGetData; 2762 // Download as much as possible, from earliest to latest. 2763 for (const CBlockIndex* pindex : vToFetch | std::views::reverse) { 2764 if (nodestate->vBlocksInFlight.size() >= MAX_BLOCKS_IN_TRANSIT_PER_PEER) { 2765 // Can't download any more from this peer 2766 break; 2767 } 2768 uint32_t nFetchFlags = GetFetchFlags(peer); 2769 vGetData.emplace_back(MSG_BLOCK | nFetchFlags, pindex->GetBlockHash()); 2770 BlockRequested(pfrom.GetId(), *pindex); 2771 LogDebug(BCLog::NET, "Requesting block %s from peer=%d\n", 2772 pindex->GetBlockHash().ToString(), pfrom.GetId()); 2773 } 2774 if (vGetData.size() > 1) { 2775 LogDebug(BCLog::NET, "Downloading blocks toward %s (%d) via headers direct fetch\n", 2776 last_header.GetBlockHash().ToString(), 2777 last_header.nHeight); 2778 } 2779 if (vGetData.size() > 0) { 2780 if (!m_opts.ignore_incoming_txs && 2781 nodestate->m_provides_cmpctblocks && 2782 vGetData.size() == 1 && 2783 mapBlocksInFlight.size() == 1 && 2784 last_header.pprev->IsValid(BLOCK_VALID_CHAIN)) { 2785 // In any case, we want to download using a compact block, not a regular one 2786 vGetData[0] = CInv(MSG_CMPCT_BLOCK, vGetData[0].hash); 2787 } 2788 MakeAndPushMessage(pfrom, NetMsgType::GETDATA, vGetData); 2789 } 2790 } 2791 } 2792 } 2793 2794 /** 2795 * Given receipt of headers from a peer ending in last_header, along with 2796 * whether that header was new and whether the headers message was full, 2797 * update the state we keep for the peer. 2798 */ 2799 void PeerManagerImpl::UpdatePeerStateForReceivedHeaders(CNode& pfrom, Peer& peer, 2800 const CBlockIndex& last_header, bool received_new_header, bool may_have_more_headers) 2801 { 2802 LOCK(cs_main); 2803 CNodeState *nodestate = State(pfrom.GetId()); 2804 2805 UpdateBlockAvailability(pfrom.GetId(), last_header.GetBlockHash()); 2806 2807 // From here, pindexBestKnownBlock should be guaranteed to be non-null, 2808 // because it is set in UpdateBlockAvailability. Some nullptr checks 2809 // are still present, however, as belt-and-suspenders. 2810 2811 if (received_new_header && last_header.nChainWork > m_chainman.ActiveChain().Tip()->nChainWork) { 2812 nodestate->m_last_block_announcement = GetTime(); 2813 } 2814 2815 // If we're in IBD, we want outbound peers that will serve us a useful 2816 // chain. Disconnect peers that are on chains with insufficient work. 2817 if (m_chainman.IsInitialBlockDownload() && !may_have_more_headers) { 2818 // If the peer has no more headers to give us, then we know we have 2819 // their tip. 2820 if (nodestate->pindexBestKnownBlock && nodestate->pindexBestKnownBlock->nChainWork < m_chainman.MinimumChainWork()) { 2821 // This peer has too little work on their headers chain to help 2822 // us sync -- disconnect if it is an outbound disconnection 2823 // candidate. 2824 // Note: We compare their tip to the minimum chain work (rather than 2825 // m_chainman.ActiveChain().Tip()) because we won't start block download 2826 // until we have a headers chain that has at least 2827 // the minimum chain work, even if a peer has a chain past our tip, 2828 // as an anti-DoS measure. 2829 if (pfrom.IsOutboundOrBlockRelayConn()) { 2830 LogInfo("outbound peer headers chain has insufficient work, %s\n", pfrom.DisconnectMsg(fLogIPs)); 2831 pfrom.fDisconnect = true; 2832 } 2833 } 2834 } 2835 2836 // If this is an outbound full-relay peer, check to see if we should protect 2837 // it from the bad/lagging chain logic. 2838 // Note that outbound block-relay peers are excluded from this protection, and 2839 // thus always subject to eviction under the bad/lagging chain logic. 2840 // See ChainSyncTimeoutState. 2841 if (!pfrom.fDisconnect && pfrom.IsFullOutboundConn() && nodestate->pindexBestKnownBlock != nullptr) { 2842 if (m_outbound_peers_with_protect_from_disconnect < MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT && nodestate->pindexBestKnownBlock->nChainWork >= m_chainman.ActiveChain().Tip()->nChainWork && !nodestate->m_chain_sync.m_protect) { 2843 LogDebug(BCLog::NET, "Protecting outbound peer=%d from eviction\n", pfrom.GetId()); 2844 nodestate->m_chain_sync.m_protect = true; 2845 ++m_outbound_peers_with_protect_from_disconnect; 2846 } 2847 } 2848 } 2849 2850 void PeerManagerImpl::ProcessHeadersMessage(CNode& pfrom, Peer& peer, 2851 std::vector<CBlockHeader>&& headers, 2852 bool via_compact_block) 2853 { 2854 size_t nCount = headers.size(); 2855 2856 if (nCount == 0) { 2857 // Nothing interesting. Stop asking this peers for more headers. 2858 // If we were in the middle of headers sync, receiving an empty headers 2859 // message suggests that the peer suddenly has nothing to give us 2860 // (perhaps it reorged to our chain). Clear download state for this peer. 2861 LOCK(peer.m_headers_sync_mutex); 2862 if (peer.m_headers_sync) { 2863 peer.m_headers_sync.reset(nullptr); 2864 LOCK(m_headers_presync_mutex); 2865 m_headers_presync_stats.erase(pfrom.GetId()); 2866 } 2867 // A headers message with no headers cannot be an announcement, so assume 2868 // it is a response to our last getheaders request, if there is one. 2869 peer.m_last_getheaders_timestamp = {}; 2870 return; 2871 } 2872 2873 // Before we do any processing, make sure these pass basic sanity checks. 2874 // We'll rely on headers having valid proof-of-work further down, as an 2875 // anti-DoS criteria (note: this check is required before passing any 2876 // headers into HeadersSyncState). 2877 if (!CheckHeadersPoW(headers, m_chainparams.GetConsensus(), peer)) { 2878 // Misbehaving() calls are handled within CheckHeadersPoW(), so we can 2879 // just return. (Note that even if a header is announced via compact 2880 // block, the header itself should be valid, so this type of error can 2881 // always be punished.) 2882 return; 2883 } 2884 2885 const CBlockIndex *pindexLast = nullptr; 2886 2887 // We'll set already_validated_work to true if these headers are 2888 // successfully processed as part of a low-work headers sync in progress 2889 // (either in PRESYNC or REDOWNLOAD phase). 2890 // If true, this will mean that any headers returned to us (ie during 2891 // REDOWNLOAD) can be validated without further anti-DoS checks. 2892 bool already_validated_work = false; 2893 2894 // If we're in the middle of headers sync, let it do its magic. 2895 bool have_headers_sync = false; 2896 { 2897 LOCK(peer.m_headers_sync_mutex); 2898 2899 already_validated_work = IsContinuationOfLowWorkHeadersSync(peer, pfrom, headers); 2900 2901 // The headers we passed in may have been: 2902 // - untouched, perhaps if no headers-sync was in progress, or some 2903 // failure occurred 2904 // - erased, such as if the headers were successfully processed and no 2905 // additional headers processing needs to take place (such as if we 2906 // are still in PRESYNC) 2907 // - replaced with headers that are now ready for validation, such as 2908 // during the REDOWNLOAD phase of a low-work headers sync. 2909 // So just check whether we still have headers that we need to process, 2910 // or not. 2911 if (headers.empty()) { 2912 return; 2913 } 2914 2915 have_headers_sync = !!peer.m_headers_sync; 2916 } 2917 2918 // Do these headers connect to something in our block index? 2919 const CBlockIndex *chain_start_header{WITH_LOCK(::cs_main, return m_chainman.m_blockman.LookupBlockIndex(headers[0].hashPrevBlock))}; 2920 bool headers_connect_blockindex{chain_start_header != nullptr}; 2921 2922 if (!headers_connect_blockindex) { 2923 // This could be a BIP 130 block announcement, use 2924 // special logic for handling headers that don't connect, as this 2925 // could be benign. 2926 HandleUnconnectingHeaders(pfrom, peer, headers); 2927 return; 2928 } 2929 2930 // If headers connect, assume that this is in response to any outstanding getheaders 2931 // request we may have sent, and clear out the time of our last request. Non-connecting 2932 // headers cannot be a response to a getheaders request. 2933 peer.m_last_getheaders_timestamp = {}; 2934 2935 // If the headers we received are already in memory and an ancestor of 2936 // m_best_header or our tip, skip anti-DoS checks. These headers will not 2937 // use any more memory (and we are not leaking information that could be 2938 // used to fingerprint us). 2939 const CBlockIndex *last_received_header{nullptr}; 2940 { 2941 LOCK(cs_main); 2942 last_received_header = m_chainman.m_blockman.LookupBlockIndex(headers.back().GetHash()); 2943 if (IsAncestorOfBestHeaderOrTip(last_received_header)) { 2944 already_validated_work = true; 2945 } 2946 } 2947 2948 // If our peer has NetPermissionFlags::NoBan privileges, then bypass our 2949 // anti-DoS logic (this saves bandwidth when we connect to a trusted peer 2950 // on startup). 2951 if (pfrom.HasPermission(NetPermissionFlags::NoBan)) { 2952 already_validated_work = true; 2953 } 2954 2955 // At this point, the headers connect to something in our block index. 2956 // Do anti-DoS checks to determine if we should process or store for later 2957 // processing. 2958 if (!already_validated_work && TryLowWorkHeadersSync(peer, pfrom, 2959 chain_start_header, headers)) { 2960 // If we successfully started a low-work headers sync, then there 2961 // should be no headers to process any further. 2962 Assume(headers.empty()); 2963 return; 2964 } 2965 2966 // At this point, we have a set of headers with sufficient work on them 2967 // which can be processed. 2968 2969 // If we don't have the last header, then this peer will have given us 2970 // something new (if these headers are valid). 2971 bool received_new_header{last_received_header == nullptr}; 2972 2973 // Now process all the headers. 2974 BlockValidationState state; 2975 const bool processed{m_chainman.ProcessNewBlockHeaders(headers, 2976 /*min_pow_checked=*/true, 2977 state, &pindexLast)}; 2978 if (!processed) { 2979 if (state.IsInvalid()) { 2980 MaybePunishNodeForBlock(pfrom.GetId(), state, via_compact_block, "invalid header received"); 2981 return; 2982 } 2983 } 2984 assert(pindexLast); 2985 2986 if (processed && received_new_header) { 2987 LogBlockHeader(*pindexLast, pfrom, /*via_compact_block=*/false); 2988 } 2989 2990 // Consider fetching more headers if we are not using our headers-sync mechanism. 2991 if (nCount == m_opts.max_headers_result && !have_headers_sync) { 2992 // Headers message had its maximum size; the peer may have more headers. 2993 if (MaybeSendGetHeaders(pfrom, GetLocator(pindexLast), peer)) { 2994 LogDebug(BCLog::NET, "more getheaders (%d) to end to peer=%d (startheight:%d)\n", 2995 pindexLast->nHeight, pfrom.GetId(), peer.m_starting_height); 2996 } 2997 } 2998 2999 UpdatePeerStateForReceivedHeaders(pfrom, peer, *pindexLast, received_new_header, nCount == m_opts.max_headers_result); 3000 3001 // Consider immediately downloading blocks. 3002 HeadersDirectFetchBlocks(pfrom, peer, *pindexLast); 3003 3004 return; 3005 } 3006 3007 std::optional<node::PackageToValidate> PeerManagerImpl::ProcessInvalidTx(NodeId nodeid, const CTransactionRef& ptx, const TxValidationState& state, 3008 bool first_time_failure) 3009 { 3010 AssertLockNotHeld(m_peer_mutex); 3011 AssertLockHeld(g_msgproc_mutex); 3012 AssertLockHeld(m_tx_download_mutex); 3013 3014 PeerRef peer{GetPeerRef(nodeid)}; 3015 3016 LogDebug(BCLog::MEMPOOLREJ, "%s (wtxid=%s) from peer=%d was not accepted: %s\n", 3017 ptx->GetHash().ToString(), 3018 ptx->GetWitnessHash().ToString(), 3019 nodeid, 3020 state.ToString()); 3021 3022 const auto& [add_extra_compact_tx, unique_parents, package_to_validate] = m_txdownloadman.MempoolRejectedTx(ptx, state, nodeid, first_time_failure); 3023 3024 if (add_extra_compact_tx && RecursiveDynamicUsage(*ptx) < 100000) { 3025 AddToCompactExtraTransactions(ptx); 3026 } 3027 for (const Txid& parent_txid : unique_parents) { 3028 if (peer) AddKnownTx(*peer, parent_txid); 3029 } 3030 3031 MaybePunishNodeForTx(nodeid, state); 3032 3033 return package_to_validate; 3034 } 3035 3036 void PeerManagerImpl::ProcessValidTx(NodeId nodeid, const CTransactionRef& tx, const std::list<CTransactionRef>& replaced_transactions) 3037 { 3038 AssertLockNotHeld(m_peer_mutex); 3039 AssertLockHeld(g_msgproc_mutex); 3040 AssertLockHeld(m_tx_download_mutex); 3041 3042 m_txdownloadman.MempoolAcceptedTx(tx); 3043 3044 LogDebug(BCLog::MEMPOOL, "AcceptToMemoryPool: peer=%d: accepted %s (wtxid=%s) (poolsz %u txn, %u kB)\n", 3045 nodeid, 3046 tx->GetHash().ToString(), 3047 tx->GetWitnessHash().ToString(), 3048 m_mempool.size(), m_mempool.DynamicMemoryUsage() / 1000); 3049 3050 RelayTransaction(tx->GetHash(), tx->GetWitnessHash()); 3051 3052 for (const CTransactionRef& removedTx : replaced_transactions) { 3053 AddToCompactExtraTransactions(removedTx); 3054 } 3055 } 3056 3057 void PeerManagerImpl::ProcessPackageResult(const node::PackageToValidate& package_to_validate, const PackageMempoolAcceptResult& package_result) 3058 { 3059 AssertLockNotHeld(m_peer_mutex); 3060 AssertLockHeld(g_msgproc_mutex); 3061 AssertLockHeld(m_tx_download_mutex); 3062 3063 const auto& package = package_to_validate.m_txns; 3064 const auto& senders = package_to_validate.m_senders; 3065 3066 if (package_result.m_state.IsInvalid()) { 3067 m_txdownloadman.MempoolRejectedPackage(package); 3068 } 3069 // We currently only expect to process 1-parent-1-child packages. Remove if this changes. 3070 if (!Assume(package.size() == 2)) return; 3071 3072 // Iterate backwards to erase in-package descendants from the orphanage before they become 3073 // relevant in AddChildrenToWorkSet. 3074 auto package_iter = package.rbegin(); 3075 auto senders_iter = senders.rbegin(); 3076 while (package_iter != package.rend()) { 3077 const auto& tx = *package_iter; 3078 const NodeId nodeid = *senders_iter; 3079 const auto it_result{package_result.m_tx_results.find(tx->GetWitnessHash())}; 3080 3081 // It is not guaranteed that a result exists for every transaction. 3082 if (it_result != package_result.m_tx_results.end()) { 3083 const auto& tx_result = it_result->second; 3084 switch (tx_result.m_result_type) { 3085 case MempoolAcceptResult::ResultType::VALID: 3086 { 3087 ProcessValidTx(nodeid, tx, tx_result.m_replaced_transactions); 3088 break; 3089 } 3090 case MempoolAcceptResult::ResultType::INVALID: 3091 case MempoolAcceptResult::ResultType::DIFFERENT_WITNESS: 3092 { 3093 // Don't add to vExtraTxnForCompact, as these transactions should have already been 3094 // added there when added to the orphanage or rejected for TX_RECONSIDERABLE. 3095 // This should be updated if package submission is ever used for transactions 3096 // that haven't already been validated before. 3097 ProcessInvalidTx(nodeid, tx, tx_result.m_state, /*first_time_failure=*/false); 3098 break; 3099 } 3100 case MempoolAcceptResult::ResultType::MEMPOOL_ENTRY: 3101 { 3102 // AlreadyHaveTx() should be catching transactions that are already in mempool. 3103 Assume(false); 3104 break; 3105 } 3106 } 3107 } 3108 package_iter++; 3109 senders_iter++; 3110 } 3111 } 3112 3113 // NOTE: the orphan processing used to be uninterruptible and quadratic, which could allow a peer to stall the node for 3114 // hours with specially crafted transactions. See https://bitcoincore.org/en/2024/07/03/disclose-orphan-dos. 3115 bool PeerManagerImpl::ProcessOrphanTx(Peer& peer) 3116 { 3117 AssertLockHeld(g_msgproc_mutex); 3118 LOCK2(::cs_main, m_tx_download_mutex); 3119 3120 CTransactionRef porphanTx = nullptr; 3121 3122 while (CTransactionRef porphanTx = m_txdownloadman.GetTxToReconsider(peer.m_id)) { 3123 const MempoolAcceptResult result = m_chainman.ProcessTransaction(porphanTx); 3124 const TxValidationState& state = result.m_state; 3125 const Txid& orphanHash = porphanTx->GetHash(); 3126 const Wtxid& orphan_wtxid = porphanTx->GetWitnessHash(); 3127 3128 if (result.m_result_type == MempoolAcceptResult::ResultType::VALID) { 3129 LogDebug(BCLog::TXPACKAGES, " accepted orphan tx %s (wtxid=%s)\n", orphanHash.ToString(), orphan_wtxid.ToString()); 3130 ProcessValidTx(peer.m_id, porphanTx, result.m_replaced_transactions); 3131 return true; 3132 } else if (state.GetResult() != TxValidationResult::TX_MISSING_INPUTS) { 3133 LogDebug(BCLog::TXPACKAGES, " invalid orphan tx %s (wtxid=%s) from peer=%d. %s\n", 3134 orphanHash.ToString(), 3135 orphan_wtxid.ToString(), 3136 peer.m_id, 3137 state.ToString()); 3138 3139 if (Assume(state.IsInvalid() && 3140 state.GetResult() != TxValidationResult::TX_UNKNOWN && 3141 state.GetResult() != TxValidationResult::TX_NO_MEMPOOL && 3142 state.GetResult() != TxValidationResult::TX_RESULT_UNSET)) { 3143 ProcessInvalidTx(peer.m_id, porphanTx, state, /*first_time_failure=*/false); 3144 } 3145 return true; 3146 } 3147 } 3148 3149 return false; 3150 } 3151 3152 bool PeerManagerImpl::PrepareBlockFilterRequest(CNode& node, Peer& peer, 3153 BlockFilterType filter_type, uint32_t start_height, 3154 const uint256& stop_hash, uint32_t max_height_diff, 3155 const CBlockIndex*& stop_index, 3156 BlockFilterIndex*& filter_index) 3157 { 3158 const bool supported_filter_type = 3159 (filter_type == BlockFilterType::BASIC && 3160 (peer.m_our_services & NODE_COMPACT_FILTERS)); 3161 if (!supported_filter_type) { 3162 LogDebug(BCLog::NET, "peer requested unsupported block filter type: %d, %s\n", 3163 static_cast<uint8_t>(filter_type), node.DisconnectMsg(fLogIPs)); 3164 node.fDisconnect = true; 3165 return false; 3166 } 3167 3168 { 3169 LOCK(cs_main); 3170 stop_index = m_chainman.m_blockman.LookupBlockIndex(stop_hash); 3171 3172 // Check that the stop block exists and the peer would be allowed to fetch it. 3173 if (!stop_index || !BlockRequestAllowed(stop_index)) { 3174 LogDebug(BCLog::NET, "peer requested invalid block hash: %s, %s\n", 3175 stop_hash.ToString(), node.DisconnectMsg(fLogIPs)); 3176 node.fDisconnect = true; 3177 return false; 3178 } 3179 } 3180 3181 uint32_t stop_height = stop_index->nHeight; 3182 if (start_height > stop_height) { 3183 LogDebug(BCLog::NET, "peer sent invalid getcfilters/getcfheaders with " 3184 "start height %d and stop height %d, %s\n", 3185 start_height, stop_height, node.DisconnectMsg(fLogIPs)); 3186 node.fDisconnect = true; 3187 return false; 3188 } 3189 if (stop_height - start_height >= max_height_diff) { 3190 LogDebug(BCLog::NET, "peer requested too many cfilters/cfheaders: %d / %d, %s\n", 3191 stop_height - start_height + 1, max_height_diff, node.DisconnectMsg(fLogIPs)); 3192 node.fDisconnect = true; 3193 return false; 3194 } 3195 3196 filter_index = GetBlockFilterIndex(filter_type); 3197 if (!filter_index) { 3198 LogDebug(BCLog::NET, "Filter index for supported type %s not found\n", BlockFilterTypeName(filter_type)); 3199 return false; 3200 } 3201 3202 return true; 3203 } 3204 3205 void PeerManagerImpl::ProcessGetCFilters(CNode& node, Peer& peer, DataStream& vRecv) 3206 { 3207 uint8_t filter_type_ser; 3208 uint32_t start_height; 3209 uint256 stop_hash; 3210 3211 vRecv >> filter_type_ser >> start_height >> stop_hash; 3212 3213 const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser); 3214 3215 const CBlockIndex* stop_index; 3216 BlockFilterIndex* filter_index; 3217 if (!PrepareBlockFilterRequest(node, peer, filter_type, start_height, stop_hash, 3218 MAX_GETCFILTERS_SIZE, stop_index, filter_index)) { 3219 return; 3220 } 3221 3222 std::vector<BlockFilter> filters; 3223 if (!filter_index->LookupFilterRange(start_height, stop_index, filters)) { 3224 LogDebug(BCLog::NET, "Failed to find block filter in index: filter_type=%s, start_height=%d, stop_hash=%s\n", 3225 BlockFilterTypeName(filter_type), start_height, stop_hash.ToString()); 3226 return; 3227 } 3228 3229 for (const auto& filter : filters) { 3230 MakeAndPushMessage(node, NetMsgType::CFILTER, filter); 3231 } 3232 } 3233 3234 void PeerManagerImpl::ProcessGetCFHeaders(CNode& node, Peer& peer, DataStream& vRecv) 3235 { 3236 uint8_t filter_type_ser; 3237 uint32_t start_height; 3238 uint256 stop_hash; 3239 3240 vRecv >> filter_type_ser >> start_height >> stop_hash; 3241 3242 const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser); 3243 3244 const CBlockIndex* stop_index; 3245 BlockFilterIndex* filter_index; 3246 if (!PrepareBlockFilterRequest(node, peer, filter_type, start_height, stop_hash, 3247 MAX_GETCFHEADERS_SIZE, stop_index, filter_index)) { 3248 return; 3249 } 3250 3251 uint256 prev_header; 3252 if (start_height > 0) { 3253 const CBlockIndex* const prev_block = 3254 stop_index->GetAncestor(static_cast<int>(start_height - 1)); 3255 if (!filter_index->LookupFilterHeader(prev_block, prev_header)) { 3256 LogDebug(BCLog::NET, "Failed to find block filter header in index: filter_type=%s, block_hash=%s\n", 3257 BlockFilterTypeName(filter_type), prev_block->GetBlockHash().ToString()); 3258 return; 3259 } 3260 } 3261 3262 std::vector<uint256> filter_hashes; 3263 if (!filter_index->LookupFilterHashRange(start_height, stop_index, filter_hashes)) { 3264 LogDebug(BCLog::NET, "Failed to find block filter hashes in index: filter_type=%s, start_height=%d, stop_hash=%s\n", 3265 BlockFilterTypeName(filter_type), start_height, stop_hash.ToString()); 3266 return; 3267 } 3268 3269 MakeAndPushMessage(node, NetMsgType::CFHEADERS, 3270 filter_type_ser, 3271 stop_index->GetBlockHash(), 3272 prev_header, 3273 filter_hashes); 3274 } 3275 3276 void PeerManagerImpl::ProcessGetCFCheckPt(CNode& node, Peer& peer, DataStream& vRecv) 3277 { 3278 uint8_t filter_type_ser; 3279 uint256 stop_hash; 3280 3281 vRecv >> filter_type_ser >> stop_hash; 3282 3283 const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser); 3284 3285 const CBlockIndex* stop_index; 3286 BlockFilterIndex* filter_index; 3287 if (!PrepareBlockFilterRequest(node, peer, filter_type, /*start_height=*/0, stop_hash, 3288 /*max_height_diff=*/std::numeric_limits<uint32_t>::max(), 3289 stop_index, filter_index)) { 3290 return; 3291 } 3292 3293 std::vector<uint256> headers(stop_index->nHeight / CFCHECKPT_INTERVAL); 3294 3295 // Populate headers. 3296 const CBlockIndex* block_index = stop_index; 3297 for (int i = headers.size() - 1; i >= 0; i--) { 3298 int height = (i + 1) * CFCHECKPT_INTERVAL; 3299 block_index = block_index->GetAncestor(height); 3300 3301 if (!filter_index->LookupFilterHeader(block_index, headers[i])) { 3302 LogDebug(BCLog::NET, "Failed to find block filter header in index: filter_type=%s, block_hash=%s\n", 3303 BlockFilterTypeName(filter_type), block_index->GetBlockHash().ToString()); 3304 return; 3305 } 3306 } 3307 3308 MakeAndPushMessage(node, NetMsgType::CFCHECKPT, 3309 filter_type_ser, 3310 stop_index->GetBlockHash(), 3311 headers); 3312 } 3313 3314 void PeerManagerImpl::ProcessBlock(CNode& node, const std::shared_ptr<const CBlock>& block, bool force_processing, bool min_pow_checked) 3315 { 3316 bool new_block{false}; 3317 m_chainman.ProcessNewBlock(block, force_processing, min_pow_checked, &new_block); 3318 if (new_block) { 3319 node.m_last_block_time = GetTime<std::chrono::seconds>(); 3320 // In case this block came from a different peer than we requested 3321 // from, we can erase the block request now anyway (as we just stored 3322 // this block to disk). 3323 LOCK(cs_main); 3324 RemoveBlockRequest(block->GetHash(), std::nullopt); 3325 } else { 3326 LOCK(cs_main); 3327 mapBlockSource.erase(block->GetHash()); 3328 } 3329 } 3330 3331 void PeerManagerImpl::ProcessCompactBlockTxns(CNode& pfrom, Peer& peer, const BlockTransactions& block_transactions) 3332 { 3333 std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); 3334 bool fBlockRead{false}; 3335 { 3336 LOCK(cs_main); 3337 3338 auto range_flight = mapBlocksInFlight.equal_range(block_transactions.blockhash); 3339 size_t already_in_flight = std::distance(range_flight.first, range_flight.second); 3340 bool requested_block_from_this_peer{false}; 3341 3342 // Multimap ensures ordering of outstanding requests. It's either empty or first in line. 3343 bool first_in_flight = already_in_flight == 0 || (range_flight.first->second.first == pfrom.GetId()); 3344 3345 while (range_flight.first != range_flight.second) { 3346 auto [node_id, block_it] = range_flight.first->second; 3347 if (node_id == pfrom.GetId() && block_it->partialBlock) { 3348 requested_block_from_this_peer = true; 3349 break; 3350 } 3351 range_flight.first++; 3352 } 3353 3354 if (!requested_block_from_this_peer) { 3355 LogDebug(BCLog::NET, "Peer %d sent us block transactions for block we weren't expecting\n", pfrom.GetId()); 3356 return; 3357 } 3358 3359 PartiallyDownloadedBlock& partialBlock = *range_flight.first->second.second->partialBlock; 3360 ReadStatus status = partialBlock.FillBlock(*pblock, block_transactions.txn); 3361 if (status == READ_STATUS_INVALID) { 3362 RemoveBlockRequest(block_transactions.blockhash, pfrom.GetId()); // Reset in-flight state in case Misbehaving does not result in a disconnect 3363 Misbehaving(peer, "invalid compact block/non-matching block transactions"); 3364 return; 3365 } else if (status == READ_STATUS_FAILED) { 3366 if (first_in_flight) { 3367 // Might have collided, fall back to getdata now :( 3368 std::vector<CInv> invs; 3369 invs.emplace_back(MSG_BLOCK | GetFetchFlags(peer), block_transactions.blockhash); 3370 MakeAndPushMessage(pfrom, NetMsgType::GETDATA, invs); 3371 } else { 3372 RemoveBlockRequest(block_transactions.blockhash, pfrom.GetId()); 3373 LogDebug(BCLog::NET, "Peer %d sent us a compact block but it failed to reconstruct, waiting on first download to complete\n", pfrom.GetId()); 3374 return; 3375 } 3376 } else { 3377 // Block is either okay, or possibly we received 3378 // READ_STATUS_CHECKBLOCK_FAILED. 3379 // Note that CheckBlock can only fail for one of a few reasons: 3380 // 1. bad-proof-of-work (impossible here, because we've already 3381 // accepted the header) 3382 // 2. merkleroot doesn't match the transactions given (already 3383 // caught in FillBlock with READ_STATUS_FAILED, so 3384 // impossible here) 3385 // 3. the block is otherwise invalid (eg invalid coinbase, 3386 // block is too big, too many legacy sigops, etc). 3387 // So if CheckBlock failed, #3 is the only possibility. 3388 // Under BIP 152, we don't discourage the peer unless proof of work is 3389 // invalid (we don't require all the stateless checks to have 3390 // been run). This is handled below, so just treat this as 3391 // though the block was successfully read, and rely on the 3392 // handling in ProcessNewBlock to ensure the block index is 3393 // updated, etc. 3394 RemoveBlockRequest(block_transactions.blockhash, pfrom.GetId()); // it is now an empty pointer 3395 fBlockRead = true; 3396 // mapBlockSource is used for potentially punishing peers and 3397 // updating which peers send us compact blocks, so the race 3398 // between here and cs_main in ProcessNewBlock is fine. 3399 // BIP 152 permits peers to relay compact blocks after validating 3400 // the header only; we should not punish peers if the block turns 3401 // out to be invalid. 3402 mapBlockSource.emplace(block_transactions.blockhash, std::make_pair(pfrom.GetId(), false)); 3403 } 3404 } // Don't hold cs_main when we call into ProcessNewBlock 3405 if (fBlockRead) { 3406 // Since we requested this block (it was in mapBlocksInFlight), force it to be processed, 3407 // even if it would not be a candidate for new tip (missing previous block, chain not long enough, etc) 3408 // This bypasses some anti-DoS logic in AcceptBlock (eg to prevent 3409 // disk-space attacks), but this should be safe due to the 3410 // protections in the compact block handler -- see related comment 3411 // in compact block optimistic reconstruction handling. 3412 ProcessBlock(pfrom, pblock, /*force_processing=*/true, /*min_pow_checked=*/true); 3413 } 3414 return; 3415 } 3416 3417 void PeerManagerImpl::LogBlockHeader(const CBlockIndex& index, const CNode& peer, bool via_compact_block) { 3418 // To prevent log spam, this function should only be called after it was determined that a 3419 // header is both new and valid. 3420 // 3421 // These messages are valuable for detecting potential selfish mining behavior; 3422 // if multiple displacing headers are seen near simultaneously across many 3423 // nodes in the network, this might be an indication of selfish mining. 3424 // In addition it can be used to identify peers which send us a header, but 3425 // don't followup with a complete and valid (compact) block. 3426 // Having this log by default when not in IBD ensures broad availability of 3427 // this data in case investigation is merited. 3428 const auto msg = strprintf( 3429 "Saw new %sheader hash=%s height=%d peer=%d%s", 3430 via_compact_block ? "cmpctblock " : "", 3431 index.GetBlockHash().ToString(), 3432 index.nHeight, 3433 peer.GetId(), 3434 peer.LogIP(fLogIPs) 3435 ); 3436 if (m_chainman.IsInitialBlockDownload()) { 3437 LogDebug(BCLog::VALIDATION, "%s", msg); 3438 } else { 3439 LogInfo("%s", msg); 3440 } 3441 } 3442 3443 void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, DataStream& vRecv, 3444 const std::chrono::microseconds time_received, 3445 const std::atomic<bool>& interruptMsgProc) 3446 { 3447 AssertLockHeld(g_msgproc_mutex); 3448 3449 LogDebug(BCLog::NET, "received: %s (%u bytes) peer=%d\n", SanitizeString(msg_type), vRecv.size(), pfrom.GetId()); 3450 3451 PeerRef peer = GetPeerRef(pfrom.GetId()); 3452 if (peer == nullptr) return; 3453 3454 if (msg_type == NetMsgType::VERSION) { 3455 if (pfrom.nVersion != 0) { 3456 LogDebug(BCLog::NET, "redundant version message from peer=%d\n", pfrom.GetId()); 3457 return; 3458 } 3459 3460 int64_t nTime; 3461 CService addrMe; 3462 uint64_t nNonce = 1; 3463 ServiceFlags nServices; 3464 int nVersion; 3465 std::string cleanSubVer; 3466 int starting_height = -1; 3467 bool fRelay = true; 3468 3469 vRecv >> nVersion >> Using<CustomUintFormatter<8>>(nServices) >> nTime; 3470 if (nTime < 0) { 3471 nTime = 0; 3472 } 3473 vRecv.ignore(8); // Ignore the addrMe service bits sent by the peer 3474 vRecv >> CNetAddr::V1(addrMe); 3475 if (!pfrom.IsInboundConn()) 3476 { 3477 // Overwrites potentially existing services. In contrast to this, 3478 // unvalidated services received via gossip relay in ADDR/ADDRV2 3479 // messages are only ever added but cannot replace existing ones. 3480 m_addrman.SetServices(pfrom.addr, nServices); 3481 } 3482 if (pfrom.ExpectServicesFromConn() && !HasAllDesirableServiceFlags(nServices)) 3483 { 3484 LogDebug(BCLog::NET, "peer does not offer the expected services (%08x offered, %08x expected), %s\n", 3485 nServices, 3486 GetDesirableServiceFlags(nServices), 3487 pfrom.DisconnectMsg(fLogIPs)); 3488 pfrom.fDisconnect = true; 3489 return; 3490 } 3491 3492 if (nVersion < MIN_PEER_PROTO_VERSION) { 3493 // disconnect from peers older than this proto version 3494 LogDebug(BCLog::NET, "peer using obsolete version %i, %s\n", nVersion, pfrom.DisconnectMsg(fLogIPs)); 3495 pfrom.fDisconnect = true; 3496 return; 3497 } 3498 3499 if (!vRecv.empty()) { 3500 // The version message includes information about the sending node which we don't use: 3501 // - 8 bytes (service bits) 3502 // - 16 bytes (ipv6 address) 3503 // - 2 bytes (port) 3504 vRecv.ignore(26); 3505 vRecv >> nNonce; 3506 } 3507 if (!vRecv.empty()) { 3508 std::string strSubVer; 3509 vRecv >> LIMITED_STRING(strSubVer, MAX_SUBVERSION_LENGTH); 3510 cleanSubVer = SanitizeString(strSubVer); 3511 } 3512 if (!vRecv.empty()) { 3513 vRecv >> starting_height; 3514 } 3515 if (!vRecv.empty()) 3516 vRecv >> fRelay; 3517 // Disconnect if we connected to ourself 3518 if (pfrom.IsInboundConn() && !m_connman.CheckIncomingNonce(nNonce)) 3519 { 3520 LogPrintf("connected to self at %s, disconnecting\n", pfrom.addr.ToStringAddrPort()); 3521 pfrom.fDisconnect = true; 3522 return; 3523 } 3524 3525 if (pfrom.IsInboundConn() && addrMe.IsRoutable()) 3526 { 3527 SeenLocal(addrMe); 3528 } 3529 3530 // Inbound peers send us their version message when they connect. 3531 // We send our version message in response. 3532 if (pfrom.IsInboundConn()) { 3533 PushNodeVersion(pfrom, *peer); 3534 } 3535 3536 // Change version 3537 const int greatest_common_version = std::min(nVersion, PROTOCOL_VERSION); 3538 pfrom.SetCommonVersion(greatest_common_version); 3539 pfrom.nVersion = nVersion; 3540 3541 if (greatest_common_version >= WTXID_RELAY_VERSION) { 3542 MakeAndPushMessage(pfrom, NetMsgType::WTXIDRELAY); 3543 } 3544 3545 // Signal ADDRv2 support (BIP155). 3546 if (greatest_common_version >= 70016) { 3547 // BIP155 defines addrv2 and sendaddrv2 for all protocol versions, but some 3548 // implementations reject messages they don't know. As a courtesy, don't send 3549 // it to nodes with a version before 70016, as no software is known to support 3550 // BIP155 that doesn't announce at least that protocol version number. 3551 MakeAndPushMessage(pfrom, NetMsgType::SENDADDRV2); 3552 } 3553 3554 pfrom.m_has_all_wanted_services = HasAllDesirableServiceFlags(nServices); 3555 peer->m_their_services = nServices; 3556 pfrom.SetAddrLocal(addrMe); 3557 { 3558 LOCK(pfrom.m_subver_mutex); 3559 pfrom.cleanSubVer = cleanSubVer; 3560 } 3561 peer->m_starting_height = starting_height; 3562 3563 // Only initialize the Peer::TxRelay m_relay_txs data structure if: 3564 // - this isn't an outbound block-relay-only connection, and 3565 // - this isn't an outbound feeler connection, and 3566 // - fRelay=true (the peer wishes to receive transaction announcements) 3567 // or we're offering NODE_BLOOM to this peer. NODE_BLOOM means that 3568 // the peer may turn on transaction relay later. 3569 if (!pfrom.IsBlockOnlyConn() && 3570 !pfrom.IsFeelerConn() && 3571 (fRelay || (peer->m_our_services & NODE_BLOOM))) { 3572 auto* const tx_relay = peer->SetTxRelay(); 3573 { 3574 LOCK(tx_relay->m_bloom_filter_mutex); 3575 tx_relay->m_relay_txs = fRelay; // set to true after we get the first filter* message 3576 } 3577 if (fRelay) pfrom.m_relays_txs = true; 3578 } 3579 3580 if (greatest_common_version >= WTXID_RELAY_VERSION && m_txreconciliation) { 3581 // Per BIP-330, we announce txreconciliation support if: 3582 // - protocol version per the peer's VERSION message supports WTXID_RELAY; 3583 // - transaction relay is supported per the peer's VERSION message 3584 // - this is not a block-relay-only connection and not a feeler 3585 // - this is not an addr fetch connection; 3586 // - we are not in -blocksonly mode. 3587 const auto* tx_relay = peer->GetTxRelay(); 3588 if (tx_relay && WITH_LOCK(tx_relay->m_bloom_filter_mutex, return tx_relay->m_relay_txs) && 3589 !pfrom.IsAddrFetchConn() && !m_opts.ignore_incoming_txs) { 3590 const uint64_t recon_salt = m_txreconciliation->PreRegisterPeer(pfrom.GetId()); 3591 MakeAndPushMessage(pfrom, NetMsgType::SENDTXRCNCL, 3592 TXRECONCILIATION_VERSION, recon_salt); 3593 } 3594 } 3595 3596 MakeAndPushMessage(pfrom, NetMsgType::VERACK); 3597 3598 // Potentially mark this peer as a preferred download peer. 3599 { 3600 LOCK(cs_main); 3601 CNodeState* state = State(pfrom.GetId()); 3602 state->fPreferredDownload = (!pfrom.IsInboundConn() || pfrom.HasPermission(NetPermissionFlags::NoBan)) && !pfrom.IsAddrFetchConn() && CanServeBlocks(*peer); 3603 m_num_preferred_download_peers += state->fPreferredDownload; 3604 } 3605 3606 // Attempt to initialize address relay for outbound peers and use result 3607 // to decide whether to send GETADDR, so that we don't send it to 3608 // inbound or outbound block-relay-only peers. 3609 bool send_getaddr{false}; 3610 if (!pfrom.IsInboundConn()) { 3611 send_getaddr = SetupAddressRelay(pfrom, *peer); 3612 } 3613 if (send_getaddr) { 3614 // Do a one-time address fetch to help populate/update our addrman. 3615 // If we're starting up for the first time, our addrman may be pretty 3616 // empty, so this mechanism is important to help us connect to the network. 3617 // We skip this for block-relay-only peers. We want to avoid 3618 // potentially leaking addr information and we do not want to 3619 // indicate to the peer that we will participate in addr relay. 3620 MakeAndPushMessage(pfrom, NetMsgType::GETADDR); 3621 peer->m_getaddr_sent = true; 3622 // When requesting a getaddr, accept an additional MAX_ADDR_TO_SEND addresses in response 3623 // (bypassing the MAX_ADDR_PROCESSING_TOKEN_BUCKET limit). 3624 peer->m_addr_token_bucket += MAX_ADDR_TO_SEND; 3625 } 3626 3627 if (!pfrom.IsInboundConn()) { 3628 // For non-inbound connections, we update the addrman to record 3629 // connection success so that addrman will have an up-to-date 3630 // notion of which peers are online and available. 3631 // 3632 // While we strive to not leak information about block-relay-only 3633 // connections via the addrman, not moving an address to the tried 3634 // table is also potentially detrimental because new-table entries 3635 // are subject to eviction in the event of addrman collisions. We 3636 // mitigate the information-leak by never calling 3637 // AddrMan::Connected() on block-relay-only peers; see 3638 // FinalizeNode(). 3639 // 3640 // This moves an address from New to Tried table in Addrman, 3641 // resolves tried-table collisions, etc. 3642 m_addrman.Good(pfrom.addr); 3643 } 3644 3645 const auto mapped_as{m_connman.GetMappedAS(pfrom.addr)}; 3646 LogDebug(BCLog::NET, "receive version message: %s: version %d, blocks=%d, us=%s, txrelay=%d, peer=%d%s%s\n", 3647 cleanSubVer, pfrom.nVersion, 3648 peer->m_starting_height, addrMe.ToStringAddrPort(), fRelay, pfrom.GetId(), 3649 pfrom.LogIP(fLogIPs), (mapped_as ? strprintf(", mapped_as=%d", mapped_as) : "")); 3650 3651 peer->m_time_offset = NodeSeconds{std::chrono::seconds{nTime}} - Now<NodeSeconds>(); 3652 if (!pfrom.IsInboundConn()) { 3653 // Don't use timedata samples from inbound peers to make it 3654 // harder for others to create false warnings about our clock being out of sync. 3655 m_outbound_time_offsets.Add(peer->m_time_offset); 3656 m_outbound_time_offsets.WarnIfOutOfSync(); 3657 } 3658 3659 // If the peer is old enough to have the old alert system, send it the final alert. 3660 if (greatest_common_version <= 70012) { 3661 constexpr auto finalAlert{"60010000000000000000000000ffffff7f00000000ffffff7ffeffff7f01ffffff7f00000000ffffff7f00ffffff7f002f555247454e543a20416c657274206b657920636f6d70726f6d697365642c2075706772616465207265717569726564004630440220653febd6410f470f6bae11cad19c48413becb1ac2c17f908fd0fd53bdc3abd5202206d0e9c96fe88d4a0f01ed9dedae2b6f9e00da94cad0fecaae66ecf689bf71b50"_hex}; 3662 MakeAndPushMessage(pfrom, "alert", finalAlert); 3663 } 3664 3665 // Feeler connections exist only to verify if address is online. 3666 if (pfrom.IsFeelerConn()) { 3667 LogDebug(BCLog::NET, "feeler connection completed, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3668 pfrom.fDisconnect = true; 3669 } 3670 return; 3671 } 3672 3673 if (pfrom.nVersion == 0) { 3674 // Must have a version message before anything else 3675 LogDebug(BCLog::NET, "non-version message before version handshake. Message \"%s\" from peer=%d\n", SanitizeString(msg_type), pfrom.GetId()); 3676 return; 3677 } 3678 3679 if (msg_type == NetMsgType::VERACK) { 3680 if (pfrom.fSuccessfullyConnected) { 3681 LogDebug(BCLog::NET, "ignoring redundant verack message from peer=%d\n", pfrom.GetId()); 3682 return; 3683 } 3684 3685 // Log successful connections unconditionally for outbound, but not for inbound as those 3686 // can be triggered by an attacker at high rate. 3687 if (!pfrom.IsInboundConn() || LogAcceptCategory(BCLog::NET, BCLog::Level::Debug)) { 3688 const auto mapped_as{m_connman.GetMappedAS(pfrom.addr)}; 3689 LogPrintf("New %s %s peer connected: version: %d, blocks=%d, peer=%d%s%s\n", 3690 pfrom.ConnectionTypeAsString(), 3691 TransportTypeAsString(pfrom.m_transport->GetInfo().transport_type), 3692 pfrom.nVersion.load(), peer->m_starting_height, 3693 pfrom.GetId(), pfrom.LogIP(fLogIPs), 3694 (mapped_as ? strprintf(", mapped_as=%d", mapped_as) : "")); 3695 } 3696 3697 if (pfrom.GetCommonVersion() >= SHORT_IDS_BLOCKS_VERSION) { 3698 // Tell our peer we are willing to provide version 2 cmpctblocks. 3699 // However, we do not request new block announcements using 3700 // cmpctblock messages. 3701 // We send this to non-NODE NETWORK peers as well, because 3702 // they may wish to request compact blocks from us 3703 MakeAndPushMessage(pfrom, NetMsgType::SENDCMPCT, /*high_bandwidth=*/false, /*version=*/CMPCTBLOCKS_VERSION); 3704 } 3705 3706 if (m_txreconciliation) { 3707 if (!peer->m_wtxid_relay || !m_txreconciliation->IsPeerRegistered(pfrom.GetId())) { 3708 // We could have optimistically pre-registered/registered the peer. In that case, 3709 // we should forget about the reconciliation state here if this wasn't followed 3710 // by WTXIDRELAY (since WTXIDRELAY can't be announced later). 3711 m_txreconciliation->ForgetPeer(pfrom.GetId()); 3712 } 3713 } 3714 3715 if (auto tx_relay = peer->GetTxRelay()) { 3716 // `TxRelay::m_tx_inventory_to_send` must be empty before the 3717 // version handshake is completed as 3718 // `TxRelay::m_next_inv_send_time` is first initialised in 3719 // `SendMessages` after the verack is received. Any transactions 3720 // received during the version handshake would otherwise 3721 // immediately be advertised without random delay, potentially 3722 // leaking the time of arrival to a spy. 3723 Assume(WITH_LOCK( 3724 tx_relay->m_tx_inventory_mutex, 3725 return tx_relay->m_tx_inventory_to_send.empty() && 3726 tx_relay->m_next_inv_send_time == 0s)); 3727 } 3728 3729 { 3730 LOCK2(::cs_main, m_tx_download_mutex); 3731 const CNodeState* state = State(pfrom.GetId()); 3732 m_txdownloadman.ConnectedPeer(pfrom.GetId(), node::TxDownloadConnectionInfo { 3733 .m_preferred = state->fPreferredDownload, 3734 .m_relay_permissions = pfrom.HasPermission(NetPermissionFlags::Relay), 3735 .m_wtxid_relay = peer->m_wtxid_relay, 3736 }); 3737 } 3738 3739 pfrom.fSuccessfullyConnected = true; 3740 return; 3741 } 3742 3743 if (msg_type == NetMsgType::SENDHEADERS) { 3744 peer->m_prefers_headers = true; 3745 return; 3746 } 3747 3748 if (msg_type == NetMsgType::SENDCMPCT) { 3749 bool sendcmpct_hb{false}; 3750 uint64_t sendcmpct_version{0}; 3751 vRecv >> sendcmpct_hb >> sendcmpct_version; 3752 3753 // Only support compact block relay with witnesses 3754 if (sendcmpct_version != CMPCTBLOCKS_VERSION) return; 3755 3756 LOCK(cs_main); 3757 CNodeState* nodestate = State(pfrom.GetId()); 3758 nodestate->m_provides_cmpctblocks = true; 3759 nodestate->m_requested_hb_cmpctblocks = sendcmpct_hb; 3760 // save whether peer selects us as BIP152 high-bandwidth peer 3761 // (receiving sendcmpct(1) signals high-bandwidth, sendcmpct(0) low-bandwidth) 3762 pfrom.m_bip152_highbandwidth_from = sendcmpct_hb; 3763 return; 3764 } 3765 3766 // BIP339 defines feature negotiation of wtxidrelay, which must happen between 3767 // VERSION and VERACK to avoid relay problems from switching after a connection is up. 3768 if (msg_type == NetMsgType::WTXIDRELAY) { 3769 if (pfrom.fSuccessfullyConnected) { 3770 // Disconnect peers that send a wtxidrelay message after VERACK. 3771 LogDebug(BCLog::NET, "wtxidrelay received after verack, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3772 pfrom.fDisconnect = true; 3773 return; 3774 } 3775 if (pfrom.GetCommonVersion() >= WTXID_RELAY_VERSION) { 3776 if (!peer->m_wtxid_relay) { 3777 peer->m_wtxid_relay = true; 3778 m_wtxid_relay_peers++; 3779 } else { 3780 LogDebug(BCLog::NET, "ignoring duplicate wtxidrelay from peer=%d\n", pfrom.GetId()); 3781 } 3782 } else { 3783 LogDebug(BCLog::NET, "ignoring wtxidrelay due to old common version=%d from peer=%d\n", pfrom.GetCommonVersion(), pfrom.GetId()); 3784 } 3785 return; 3786 } 3787 3788 // BIP155 defines feature negotiation of addrv2 and sendaddrv2, which must happen 3789 // between VERSION and VERACK. 3790 if (msg_type == NetMsgType::SENDADDRV2) { 3791 if (pfrom.fSuccessfullyConnected) { 3792 // Disconnect peers that send a SENDADDRV2 message after VERACK. 3793 LogDebug(BCLog::NET, "sendaddrv2 received after verack, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3794 pfrom.fDisconnect = true; 3795 return; 3796 } 3797 peer->m_wants_addrv2 = true; 3798 return; 3799 } 3800 3801 // Received from a peer demonstrating readiness to announce transactions via reconciliations. 3802 // This feature negotiation must happen between VERSION and VERACK to avoid relay problems 3803 // from switching announcement protocols after the connection is up. 3804 if (msg_type == NetMsgType::SENDTXRCNCL) { 3805 if (!m_txreconciliation) { 3806 LogDebug(BCLog::NET, "sendtxrcncl from peer=%d ignored, as our node does not have txreconciliation enabled\n", pfrom.GetId()); 3807 return; 3808 } 3809 3810 if (pfrom.fSuccessfullyConnected) { 3811 LogDebug(BCLog::NET, "sendtxrcncl received after verack, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3812 pfrom.fDisconnect = true; 3813 return; 3814 } 3815 3816 // Peer must not offer us reconciliations if we specified no tx relay support in VERSION. 3817 if (RejectIncomingTxs(pfrom)) { 3818 LogDebug(BCLog::NET, "sendtxrcncl received to which we indicated no tx relay, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3819 pfrom.fDisconnect = true; 3820 return; 3821 } 3822 3823 // Peer must not offer us reconciliations if they specified no tx relay support in VERSION. 3824 // This flag might also be false in other cases, but the RejectIncomingTxs check above 3825 // eliminates them, so that this flag fully represents what we are looking for. 3826 const auto* tx_relay = peer->GetTxRelay(); 3827 if (!tx_relay || !WITH_LOCK(tx_relay->m_bloom_filter_mutex, return tx_relay->m_relay_txs)) { 3828 LogDebug(BCLog::NET, "sendtxrcncl received which indicated no tx relay to us, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3829 pfrom.fDisconnect = true; 3830 return; 3831 } 3832 3833 uint32_t peer_txreconcl_version; 3834 uint64_t remote_salt; 3835 vRecv >> peer_txreconcl_version >> remote_salt; 3836 3837 const ReconciliationRegisterResult result = m_txreconciliation->RegisterPeer(pfrom.GetId(), pfrom.IsInboundConn(), 3838 peer_txreconcl_version, remote_salt); 3839 switch (result) { 3840 case ReconciliationRegisterResult::NOT_FOUND: 3841 LogDebug(BCLog::NET, "Ignore unexpected txreconciliation signal from peer=%d\n", pfrom.GetId()); 3842 break; 3843 case ReconciliationRegisterResult::SUCCESS: 3844 break; 3845 case ReconciliationRegisterResult::ALREADY_REGISTERED: 3846 LogDebug(BCLog::NET, "txreconciliation protocol violation (sendtxrcncl received from already registered peer), %s\n", pfrom.DisconnectMsg(fLogIPs)); 3847 pfrom.fDisconnect = true; 3848 return; 3849 case ReconciliationRegisterResult::PROTOCOL_VIOLATION: 3850 LogDebug(BCLog::NET, "txreconciliation protocol violation, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3851 pfrom.fDisconnect = true; 3852 return; 3853 } 3854 return; 3855 } 3856 3857 if (!pfrom.fSuccessfullyConnected) { 3858 LogDebug(BCLog::NET, "Unsupported message \"%s\" prior to verack from peer=%d\n", SanitizeString(msg_type), pfrom.GetId()); 3859 return; 3860 } 3861 3862 if (msg_type == NetMsgType::ADDR || msg_type == NetMsgType::ADDRV2) { 3863 const auto ser_params{ 3864 msg_type == NetMsgType::ADDRV2 ? 3865 // Set V2 param so that the CNetAddr and CAddress 3866 // unserialize methods know that an address in v2 format is coming. 3867 CAddress::V2_NETWORK : 3868 CAddress::V1_NETWORK, 3869 }; 3870 3871 std::vector<CAddress> vAddr; 3872 3873 vRecv >> ser_params(vAddr); 3874 3875 if (!SetupAddressRelay(pfrom, *peer)) { 3876 LogDebug(BCLog::NET, "ignoring %s message from %s peer=%d\n", msg_type, pfrom.ConnectionTypeAsString(), pfrom.GetId()); 3877 return; 3878 } 3879 3880 if (vAddr.size() > MAX_ADDR_TO_SEND) 3881 { 3882 Misbehaving(*peer, strprintf("%s message size = %u", msg_type, vAddr.size())); 3883 return; 3884 } 3885 3886 // Store the new addresses 3887 std::vector<CAddress> vAddrOk; 3888 const auto current_a_time{Now<NodeSeconds>()}; 3889 3890 // Update/increment addr rate limiting bucket. 3891 const auto current_time{GetTime<std::chrono::microseconds>()}; 3892 if (peer->m_addr_token_bucket < MAX_ADDR_PROCESSING_TOKEN_BUCKET) { 3893 // Don't increment bucket if it's already full 3894 const auto time_diff = std::max(current_time - peer->m_addr_token_timestamp, 0us); 3895 const double increment = Ticks<SecondsDouble>(time_diff) * MAX_ADDR_RATE_PER_SECOND; 3896 peer->m_addr_token_bucket = std::min<double>(peer->m_addr_token_bucket + increment, MAX_ADDR_PROCESSING_TOKEN_BUCKET); 3897 } 3898 peer->m_addr_token_timestamp = current_time; 3899 3900 const bool rate_limited = !pfrom.HasPermission(NetPermissionFlags::Addr); 3901 uint64_t num_proc = 0; 3902 uint64_t num_rate_limit = 0; 3903 std::shuffle(vAddr.begin(), vAddr.end(), m_rng); 3904 for (CAddress& addr : vAddr) 3905 { 3906 if (interruptMsgProc) 3907 return; 3908 3909 // Apply rate limiting. 3910 if (peer->m_addr_token_bucket < 1.0) { 3911 if (rate_limited) { 3912 ++num_rate_limit; 3913 continue; 3914 } 3915 } else { 3916 peer->m_addr_token_bucket -= 1.0; 3917 } 3918 // We only bother storing full nodes, though this may include 3919 // things which we would not make an outbound connection to, in 3920 // part because we may make feeler connections to them. 3921 if (!MayHaveUsefulAddressDB(addr.nServices) && !HasAllDesirableServiceFlags(addr.nServices)) 3922 continue; 3923 3924 if (addr.nTime <= NodeSeconds{100000000s} || addr.nTime > current_a_time + 10min) { 3925 addr.nTime = current_a_time - 5 * 24h; 3926 } 3927 AddAddressKnown(*peer, addr); 3928 if (m_banman && (m_banman->IsDiscouraged(addr) || m_banman->IsBanned(addr))) { 3929 // Do not process banned/discouraged addresses beyond remembering we received them 3930 continue; 3931 } 3932 ++num_proc; 3933 const bool reachable{g_reachable_nets.Contains(addr)}; 3934 if (addr.nTime > current_a_time - 10min && !peer->m_getaddr_sent && vAddr.size() <= 10 && addr.IsRoutable()) { 3935 // Relay to a limited number of other nodes 3936 RelayAddress(pfrom.GetId(), addr, reachable); 3937 } 3938 // Do not store addresses outside our network 3939 if (reachable) { 3940 vAddrOk.push_back(addr); 3941 } 3942 } 3943 peer->m_addr_processed += num_proc; 3944 peer->m_addr_rate_limited += num_rate_limit; 3945 LogDebug(BCLog::NET, "Received addr: %u addresses (%u processed, %u rate-limited) from peer=%d\n", 3946 vAddr.size(), num_proc, num_rate_limit, pfrom.GetId()); 3947 3948 m_addrman.Add(vAddrOk, pfrom.addr, 2h); 3949 if (vAddr.size() < 1000) peer->m_getaddr_sent = false; 3950 3951 // AddrFetch: Require multiple addresses to avoid disconnecting on self-announcements 3952 if (pfrom.IsAddrFetchConn() && vAddr.size() > 1) { 3953 LogDebug(BCLog::NET, "addrfetch connection completed, %s\n", pfrom.DisconnectMsg(fLogIPs)); 3954 pfrom.fDisconnect = true; 3955 } 3956 return; 3957 } 3958 3959 if (msg_type == NetMsgType::INV) { 3960 std::vector<CInv> vInv; 3961 vRecv >> vInv; 3962 if (vInv.size() > MAX_INV_SZ) 3963 { 3964 Misbehaving(*peer, strprintf("inv message size = %u", vInv.size())); 3965 return; 3966 } 3967 3968 const bool reject_tx_invs{RejectIncomingTxs(pfrom)}; 3969 3970 LOCK2(cs_main, m_tx_download_mutex); 3971 3972 const auto current_time{GetTime<std::chrono::microseconds>()}; 3973 uint256* best_block{nullptr}; 3974 3975 for (CInv& inv : vInv) { 3976 if (interruptMsgProc) return; 3977 3978 // Ignore INVs that don't match wtxidrelay setting. 3979 // Note that orphan parent fetching always uses MSG_TX GETDATAs regardless of the wtxidrelay setting. 3980 // This is fine as no INV messages are involved in that process. 3981 if (peer->m_wtxid_relay) { 3982 if (inv.IsMsgTx()) continue; 3983 } else { 3984 if (inv.IsMsgWtx()) continue; 3985 } 3986 3987 if (inv.IsMsgBlk()) { 3988 const bool fAlreadyHave = AlreadyHaveBlock(inv.hash); 3989 LogDebug(BCLog::NET, "got inv: %s %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom.GetId()); 3990 3991 UpdateBlockAvailability(pfrom.GetId(), inv.hash); 3992 if (!fAlreadyHave && !m_chainman.m_blockman.LoadingBlocks() && !IsBlockRequested(inv.hash)) { 3993 // Headers-first is the primary method of announcement on 3994 // the network. If a node fell back to sending blocks by 3995 // inv, it may be for a re-org, or because we haven't 3996 // completed initial headers sync. The final block hash 3997 // provided should be the highest, so send a getheaders and 3998 // then fetch the blocks we need to catch up. 3999 best_block = &inv.hash; 4000 } 4001 } else if (inv.IsGenTxMsg()) { 4002 if (reject_tx_invs) { 4003 LogDebug(BCLog::NET, "transaction (%s) inv sent in violation of protocol, %s\n", inv.hash.ToString(), pfrom.DisconnectMsg(fLogIPs)); 4004 pfrom.fDisconnect = true; 4005 return; 4006 } 4007 const GenTxid gtxid = ToGenTxid(inv); 4008 AddKnownTx(*peer, inv.hash); 4009 4010 if (!m_chainman.IsInitialBlockDownload()) { 4011 const bool fAlreadyHave{m_txdownloadman.AddTxAnnouncement(pfrom.GetId(), gtxid, current_time)}; 4012 LogDebug(BCLog::NET, "got inv: %s %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom.GetId()); 4013 } 4014 } else { 4015 LogDebug(BCLog::NET, "Unknown inv type \"%s\" received from peer=%d\n", inv.ToString(), pfrom.GetId()); 4016 } 4017 } 4018 4019 if (best_block != nullptr) { 4020 // If we haven't started initial headers-sync with this peer, then 4021 // consider sending a getheaders now. On initial startup, there's a 4022 // reliability vs bandwidth tradeoff, where we are only trying to do 4023 // initial headers sync with one peer at a time, with a long 4024 // timeout (at which point, if the sync hasn't completed, we will 4025 // disconnect the peer and then choose another). In the meantime, 4026 // as new blocks are found, we are willing to add one new peer per 4027 // block to sync with as well, to sync quicker in the case where 4028 // our initial peer is unresponsive (but less bandwidth than we'd 4029 // use if we turned on sync with all peers). 4030 CNodeState& state{*Assert(State(pfrom.GetId()))}; 4031 if (state.fSyncStarted || (!peer->m_inv_triggered_getheaders_before_sync && *best_block != m_last_block_inv_triggering_headers_sync)) { 4032 if (MaybeSendGetHeaders(pfrom, GetLocator(m_chainman.m_best_header), *peer)) { 4033 LogDebug(BCLog::NET, "getheaders (%d) %s to peer=%d\n", 4034 m_chainman.m_best_header->nHeight, best_block->ToString(), 4035 pfrom.GetId()); 4036 } 4037 if (!state.fSyncStarted) { 4038 peer->m_inv_triggered_getheaders_before_sync = true; 4039 // Update the last block hash that triggered a new headers 4040 // sync, so that we don't turn on headers sync with more 4041 // than 1 new peer every new block. 4042 m_last_block_inv_triggering_headers_sync = *best_block; 4043 } 4044 } 4045 } 4046 4047 return; 4048 } 4049 4050 if (msg_type == NetMsgType::GETDATA) { 4051 std::vector<CInv> vInv; 4052 vRecv >> vInv; 4053 if (vInv.size() > MAX_INV_SZ) 4054 { 4055 Misbehaving(*peer, strprintf("getdata message size = %u", vInv.size())); 4056 return; 4057 } 4058 4059 LogDebug(BCLog::NET, "received getdata (%u invsz) peer=%d\n", vInv.size(), pfrom.GetId()); 4060 4061 if (vInv.size() > 0) { 4062 LogDebug(BCLog::NET, "received getdata for: %s peer=%d\n", vInv[0].ToString(), pfrom.GetId()); 4063 } 4064 4065 { 4066 LOCK(peer->m_getdata_requests_mutex); 4067 peer->m_getdata_requests.insert(peer->m_getdata_requests.end(), vInv.begin(), vInv.end()); 4068 ProcessGetData(pfrom, *peer, interruptMsgProc); 4069 } 4070 4071 return; 4072 } 4073 4074 if (msg_type == NetMsgType::GETBLOCKS) { 4075 CBlockLocator locator; 4076 uint256 hashStop; 4077 vRecv >> locator >> hashStop; 4078 4079 if (locator.vHave.size() > MAX_LOCATOR_SZ) { 4080 LogDebug(BCLog::NET, "getblocks locator size %lld > %d, %s\n", locator.vHave.size(), MAX_LOCATOR_SZ, pfrom.DisconnectMsg(fLogIPs)); 4081 pfrom.fDisconnect = true; 4082 return; 4083 } 4084 4085 // We might have announced the currently-being-connected tip using a 4086 // compact block, which resulted in the peer sending a getblocks 4087 // request, which we would otherwise respond to without the new block. 4088 // To avoid this situation we simply verify that we are on our best 4089 // known chain now. This is super overkill, but we handle it better 4090 // for getheaders requests, and there are no known nodes which support 4091 // compact blocks but still use getblocks to request blocks. 4092 { 4093 std::shared_ptr<const CBlock> a_recent_block; 4094 { 4095 LOCK(m_most_recent_block_mutex); 4096 a_recent_block = m_most_recent_block; 4097 } 4098 BlockValidationState state; 4099 if (!m_chainman.ActiveChainstate().ActivateBestChain(state, a_recent_block)) { 4100 LogDebug(BCLog::NET, "failed to activate chain (%s)\n", state.ToString()); 4101 } 4102 } 4103 4104 LOCK(cs_main); 4105 4106 // Find the last block the caller has in the main chain 4107 const CBlockIndex* pindex = m_chainman.ActiveChainstate().FindForkInGlobalIndex(locator); 4108 4109 // Send the rest of the chain 4110 if (pindex) 4111 pindex = m_chainman.ActiveChain().Next(pindex); 4112 int nLimit = 500; 4113 LogDebug(BCLog::NET, "getblocks %d to %s limit %d from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop.IsNull() ? "end" : hashStop.ToString(), nLimit, pfrom.GetId()); 4114 for (; pindex; pindex = m_chainman.ActiveChain().Next(pindex)) 4115 { 4116 if (pindex->GetBlockHash() == hashStop) 4117 { 4118 LogDebug(BCLog::NET, " getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString()); 4119 break; 4120 } 4121 // If pruning, don't inv blocks unless we have on disk and are likely to still have 4122 // for some reasonable time window (1 hour) that block relay might require. 4123 const int nPrunedBlocksLikelyToHave = MIN_BLOCKS_TO_KEEP - 3600 / m_chainparams.GetConsensus().nPowTargetSpacing; 4124 if (m_chainman.m_blockman.IsPruneMode() && (!(pindex->nStatus & BLOCK_HAVE_DATA) || pindex->nHeight <= m_chainman.ActiveChain().Tip()->nHeight - nPrunedBlocksLikelyToHave)) { 4125 LogDebug(BCLog::NET, " getblocks stopping, pruned or too old block at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString()); 4126 break; 4127 } 4128 WITH_LOCK(peer->m_block_inv_mutex, peer->m_blocks_for_inv_relay.push_back(pindex->GetBlockHash())); 4129 if (--nLimit <= 0) { 4130 // When this block is requested, we'll send an inv that'll 4131 // trigger the peer to getblocks the next batch of inventory. 4132 LogDebug(BCLog::NET, " getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString()); 4133 WITH_LOCK(peer->m_block_inv_mutex, {peer->m_continuation_block = pindex->GetBlockHash();}); 4134 break; 4135 } 4136 } 4137 return; 4138 } 4139 4140 if (msg_type == NetMsgType::GETBLOCKTXN) { 4141 BlockTransactionsRequest req; 4142 vRecv >> req; 4143 4144 std::shared_ptr<const CBlock> recent_block; 4145 { 4146 LOCK(m_most_recent_block_mutex); 4147 if (m_most_recent_block_hash == req.blockhash) 4148 recent_block = m_most_recent_block; 4149 // Unlock m_most_recent_block_mutex to avoid cs_main lock inversion 4150 } 4151 if (recent_block) { 4152 SendBlockTransactions(pfrom, *peer, *recent_block, req); 4153 return; 4154 } 4155 4156 FlatFilePos block_pos{}; 4157 { 4158 LOCK(cs_main); 4159 4160 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(req.blockhash); 4161 if (!pindex || !(pindex->nStatus & BLOCK_HAVE_DATA)) { 4162 LogDebug(BCLog::NET, "Peer %d sent us a getblocktxn for a block we don't have\n", pfrom.GetId()); 4163 return; 4164 } 4165 4166 if (pindex->nHeight >= m_chainman.ActiveChain().Height() - MAX_BLOCKTXN_DEPTH) { 4167 block_pos = pindex->GetBlockPos(); 4168 } 4169 } 4170 4171 if (!block_pos.IsNull()) { 4172 CBlock block; 4173 const bool ret{m_chainman.m_blockman.ReadBlock(block, block_pos)}; 4174 // If height is above MAX_BLOCKTXN_DEPTH then this block cannot get 4175 // pruned after we release cs_main above, so this read should never fail. 4176 assert(ret); 4177 4178 SendBlockTransactions(pfrom, *peer, block, req); 4179 return; 4180 } 4181 4182 // If an older block is requested (should never happen in practice, 4183 // but can happen in tests) send a block response instead of a 4184 // blocktxn response. Sending a full block response instead of a 4185 // small blocktxn response is preferable in the case where a peer 4186 // might maliciously send lots of getblocktxn requests to trigger 4187 // expensive disk reads, because it will require the peer to 4188 // actually receive all the data read from disk over the network. 4189 LogDebug(BCLog::NET, "Peer %d sent us a getblocktxn for a block > %i deep\n", pfrom.GetId(), MAX_BLOCKTXN_DEPTH); 4190 CInv inv{MSG_WITNESS_BLOCK, req.blockhash}; 4191 WITH_LOCK(peer->m_getdata_requests_mutex, peer->m_getdata_requests.push_back(inv)); 4192 // The message processing loop will go around again (without pausing) and we'll respond then 4193 return; 4194 } 4195 4196 if (msg_type == NetMsgType::GETHEADERS) { 4197 CBlockLocator locator; 4198 uint256 hashStop; 4199 vRecv >> locator >> hashStop; 4200 4201 if (locator.vHave.size() > MAX_LOCATOR_SZ) { 4202 LogDebug(BCLog::NET, "getheaders locator size %lld > %d, %s\n", locator.vHave.size(), MAX_LOCATOR_SZ, pfrom.DisconnectMsg(fLogIPs)); 4203 pfrom.fDisconnect = true; 4204 return; 4205 } 4206 4207 if (m_chainman.m_blockman.LoadingBlocks()) { 4208 LogDebug(BCLog::NET, "Ignoring getheaders from peer=%d while importing/reindexing\n", pfrom.GetId()); 4209 return; 4210 } 4211 4212 LOCK(cs_main); 4213 4214 // Don't serve headers from our active chain until our chainwork is at least 4215 // the minimum chain work. This prevents us from starting a low-work headers 4216 // sync that will inevitably be aborted by our peer. 4217 if (m_chainman.ActiveTip() == nullptr || 4218 (m_chainman.ActiveTip()->nChainWork < m_chainman.MinimumChainWork() && !pfrom.HasPermission(NetPermissionFlags::Download))) { 4219 LogDebug(BCLog::NET, "Ignoring getheaders from peer=%d because active chain has too little work; sending empty response\n", pfrom.GetId()); 4220 // Just respond with an empty headers message, to tell the peer to 4221 // go away but not treat us as unresponsive. 4222 MakeAndPushMessage(pfrom, NetMsgType::HEADERS, std::vector<CBlockHeader>()); 4223 return; 4224 } 4225 4226 CNodeState *nodestate = State(pfrom.GetId()); 4227 const CBlockIndex* pindex = nullptr; 4228 if (locator.IsNull()) 4229 { 4230 // If locator is null, return the hashStop block 4231 pindex = m_chainman.m_blockman.LookupBlockIndex(hashStop); 4232 if (!pindex) { 4233 return; 4234 } 4235 4236 if (!BlockRequestAllowed(pindex)) { 4237 LogDebug(BCLog::NET, "%s: ignoring request from peer=%i for old block header that isn't in the main chain\n", __func__, pfrom.GetId()); 4238 return; 4239 } 4240 } 4241 else 4242 { 4243 // Find the last block the caller has in the main chain 4244 pindex = m_chainman.ActiveChainstate().FindForkInGlobalIndex(locator); 4245 if (pindex) 4246 pindex = m_chainman.ActiveChain().Next(pindex); 4247 } 4248 4249 // we must use CBlocks, as CBlockHeaders won't include the 0x00 nTx count at the end 4250 std::vector<CBlock> vHeaders; 4251 int nLimit = m_opts.max_headers_result; 4252 LogDebug(BCLog::NET, "getheaders %d to %s from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop.IsNull() ? "end" : hashStop.ToString(), pfrom.GetId()); 4253 for (; pindex; pindex = m_chainman.ActiveChain().Next(pindex)) 4254 { 4255 vHeaders.emplace_back(pindex->GetBlockHeader()); 4256 if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop) 4257 break; 4258 } 4259 // pindex can be nullptr either if we sent m_chainman.ActiveChain().Tip() OR 4260 // if our peer has m_chainman.ActiveChain().Tip() (and thus we are sending an empty 4261 // headers message). In both cases it's safe to update 4262 // pindexBestHeaderSent to be our tip. 4263 // 4264 // It is important that we simply reset the BestHeaderSent value here, 4265 // and not max(BestHeaderSent, newHeaderSent). We might have announced 4266 // the currently-being-connected tip using a compact block, which 4267 // resulted in the peer sending a headers request, which we respond to 4268 // without the new block. By resetting the BestHeaderSent, we ensure we 4269 // will re-announce the new block via headers (or compact blocks again) 4270 // in the SendMessages logic. 4271 nodestate->pindexBestHeaderSent = pindex ? pindex : m_chainman.ActiveChain().Tip(); 4272 MakeAndPushMessage(pfrom, NetMsgType::HEADERS, TX_WITH_WITNESS(vHeaders)); 4273 return; 4274 } 4275 4276 if (msg_type == NetMsgType::TX) { 4277 if (RejectIncomingTxs(pfrom)) { 4278 LogDebug(BCLog::NET, "transaction sent in violation of protocol, %s", pfrom.DisconnectMsg(fLogIPs)); 4279 pfrom.fDisconnect = true; 4280 return; 4281 } 4282 4283 // Stop processing the transaction early if we are still in IBD since we don't 4284 // have enough information to validate it yet. Sending unsolicited transactions 4285 // is not considered a protocol violation, so don't punish the peer. 4286 if (m_chainman.IsInitialBlockDownload()) return; 4287 4288 CTransactionRef ptx; 4289 vRecv >> TX_WITH_WITNESS(ptx); 4290 const CTransaction& tx = *ptx; 4291 4292 const uint256& txid = ptx->GetHash(); 4293 const uint256& wtxid = ptx->GetWitnessHash(); 4294 4295 const uint256& hash = peer->m_wtxid_relay ? wtxid : txid; 4296 AddKnownTx(*peer, hash); 4297 4298 LOCK2(cs_main, m_tx_download_mutex); 4299 4300 const auto& [should_validate, package_to_validate] = m_txdownloadman.ReceivedTx(pfrom.GetId(), ptx); 4301 if (!should_validate) { 4302 if (pfrom.HasPermission(NetPermissionFlags::ForceRelay)) { 4303 // Always relay transactions received from peers with forcerelay 4304 // permission, even if they were already in the mempool, allowing 4305 // the node to function as a gateway for nodes hidden behind it. 4306 if (!m_mempool.exists(GenTxid::Txid(tx.GetHash()))) { 4307 LogPrintf("Not relaying non-mempool transaction %s (wtxid=%s) from forcerelay peer=%d\n", 4308 tx.GetHash().ToString(), tx.GetWitnessHash().ToString(), pfrom.GetId()); 4309 } else { 4310 LogPrintf("Force relaying tx %s (wtxid=%s) from peer=%d\n", 4311 tx.GetHash().ToString(), tx.GetWitnessHash().ToString(), pfrom.GetId()); 4312 RelayTransaction(tx.GetHash(), tx.GetWitnessHash()); 4313 } 4314 } 4315 4316 if (package_to_validate) { 4317 const auto package_result{ProcessNewPackage(m_chainman.ActiveChainstate(), m_mempool, package_to_validate->m_txns, /*test_accept=*/false, /*client_maxfeerate=*/std::nullopt)}; 4318 LogDebug(BCLog::TXPACKAGES, "package evaluation for %s: %s\n", package_to_validate->ToString(), 4319 package_result.m_state.IsValid() ? "package accepted" : "package rejected"); 4320 ProcessPackageResult(package_to_validate.value(), package_result); 4321 } 4322 return; 4323 } 4324 4325 // ReceivedTx should not be telling us to validate the tx and a package. 4326 Assume(!package_to_validate.has_value()); 4327 4328 const MempoolAcceptResult result = m_chainman.ProcessTransaction(ptx); 4329 const TxValidationState& state = result.m_state; 4330 4331 if (result.m_result_type == MempoolAcceptResult::ResultType::VALID) { 4332 ProcessValidTx(pfrom.GetId(), ptx, result.m_replaced_transactions); 4333 pfrom.m_last_tx_time = GetTime<std::chrono::seconds>(); 4334 } 4335 if (state.IsInvalid()) { 4336 if (auto package_to_validate{ProcessInvalidTx(pfrom.GetId(), ptx, state, /*first_time_failure=*/true)}) { 4337 const auto package_result{ProcessNewPackage(m_chainman.ActiveChainstate(), m_mempool, package_to_validate->m_txns, /*test_accept=*/false, /*client_maxfeerate=*/std::nullopt)}; 4338 LogDebug(BCLog::TXPACKAGES, "package evaluation for %s: %s\n", package_to_validate->ToString(), 4339 package_result.m_state.IsValid() ? "package accepted" : "package rejected"); 4340 ProcessPackageResult(package_to_validate.value(), package_result); 4341 } 4342 } 4343 4344 return; 4345 } 4346 4347 if (msg_type == NetMsgType::CMPCTBLOCK) 4348 { 4349 // Ignore cmpctblock received while importing 4350 if (m_chainman.m_blockman.LoadingBlocks()) { 4351 LogDebug(BCLog::NET, "Unexpected cmpctblock message received from peer %d\n", pfrom.GetId()); 4352 return; 4353 } 4354 4355 CBlockHeaderAndShortTxIDs cmpctblock; 4356 vRecv >> cmpctblock; 4357 4358 bool received_new_header = false; 4359 const auto blockhash = cmpctblock.header.GetHash(); 4360 4361 { 4362 LOCK(cs_main); 4363 4364 const CBlockIndex* prev_block = m_chainman.m_blockman.LookupBlockIndex(cmpctblock.header.hashPrevBlock); 4365 if (!prev_block) { 4366 // Doesn't connect (or is genesis), instead of DoSing in AcceptBlockHeader, request deeper headers 4367 if (!m_chainman.IsInitialBlockDownload()) { 4368 MaybeSendGetHeaders(pfrom, GetLocator(m_chainman.m_best_header), *peer); 4369 } 4370 return; 4371 } else if (prev_block->nChainWork + CalculateClaimedHeadersWork({{cmpctblock.header}}) < GetAntiDoSWorkThreshold()) { 4372 // If we get a low-work header in a compact block, we can ignore it. 4373 LogDebug(BCLog::NET, "Ignoring low-work compact block from peer %d\n", pfrom.GetId()); 4374 return; 4375 } 4376 4377 if (!m_chainman.m_blockman.LookupBlockIndex(blockhash)) { 4378 received_new_header = true; 4379 } 4380 } 4381 4382 const CBlockIndex *pindex = nullptr; 4383 BlockValidationState state; 4384 if (!m_chainman.ProcessNewBlockHeaders({{cmpctblock.header}}, /*min_pow_checked=*/true, state, &pindex)) { 4385 if (state.IsInvalid()) { 4386 MaybePunishNodeForBlock(pfrom.GetId(), state, /*via_compact_block=*/true, "invalid header via cmpctblock"); 4387 return; 4388 } 4389 } 4390 4391 // If AcceptBlockHeader returned true, it set pindex 4392 Assert(pindex); 4393 if (received_new_header) { 4394 LogBlockHeader(*pindex, pfrom, /*via_compact_block=*/true); 4395 } 4396 4397 bool fProcessBLOCKTXN = false; 4398 4399 // If we end up treating this as a plain headers message, call that as well 4400 // without cs_main. 4401 bool fRevertToHeaderProcessing = false; 4402 4403 // Keep a CBlock for "optimistic" compactblock reconstructions (see 4404 // below) 4405 std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); 4406 bool fBlockReconstructed = false; 4407 4408 { 4409 LOCK(cs_main); 4410 UpdateBlockAvailability(pfrom.GetId(), pindex->GetBlockHash()); 4411 4412 CNodeState *nodestate = State(pfrom.GetId()); 4413 4414 // If this was a new header with more work than our tip, update the 4415 // peer's last block announcement time 4416 if (received_new_header && pindex->nChainWork > m_chainman.ActiveChain().Tip()->nChainWork) { 4417 nodestate->m_last_block_announcement = GetTime(); 4418 } 4419 4420 if (pindex->nStatus & BLOCK_HAVE_DATA) // Nothing to do here 4421 return; 4422 4423 auto range_flight = mapBlocksInFlight.equal_range(pindex->GetBlockHash()); 4424 size_t already_in_flight = std::distance(range_flight.first, range_flight.second); 4425 bool requested_block_from_this_peer{false}; 4426 4427 // Multimap ensures ordering of outstanding requests. It's either empty or first in line. 4428 bool first_in_flight = already_in_flight == 0 || (range_flight.first->second.first == pfrom.GetId()); 4429 4430 while (range_flight.first != range_flight.second) { 4431 if (range_flight.first->second.first == pfrom.GetId()) { 4432 requested_block_from_this_peer = true; 4433 break; 4434 } 4435 range_flight.first++; 4436 } 4437 4438 if (pindex->nChainWork <= m_chainman.ActiveChain().Tip()->nChainWork || // We know something better 4439 pindex->nTx != 0) { // We had this block at some point, but pruned it 4440 if (requested_block_from_this_peer) { 4441 // We requested this block for some reason, but our mempool will probably be useless 4442 // so we just grab the block via normal getdata 4443 std::vector<CInv> vInv(1); 4444 vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(*peer), blockhash); 4445 MakeAndPushMessage(pfrom, NetMsgType::GETDATA, vInv); 4446 } 4447 return; 4448 } 4449 4450 // If we're not close to tip yet, give up and let parallel block fetch work its magic 4451 if (!already_in_flight && !CanDirectFetch()) { 4452 return; 4453 } 4454 4455 // We want to be a bit conservative just to be extra careful about DoS 4456 // possibilities in compact block processing... 4457 if (pindex->nHeight <= m_chainman.ActiveChain().Height() + 2) { 4458 if ((already_in_flight < MAX_CMPCTBLOCKS_INFLIGHT_PER_BLOCK && nodestate->vBlocksInFlight.size() < MAX_BLOCKS_IN_TRANSIT_PER_PEER) || 4459 requested_block_from_this_peer) { 4460 std::list<QueuedBlock>::iterator* queuedBlockIt = nullptr; 4461 if (!BlockRequested(pfrom.GetId(), *pindex, &queuedBlockIt)) { 4462 if (!(*queuedBlockIt)->partialBlock) 4463 (*queuedBlockIt)->partialBlock.reset(new PartiallyDownloadedBlock(&m_mempool)); 4464 else { 4465 // The block was already in flight using compact blocks from the same peer 4466 LogDebug(BCLog::NET, "Peer sent us compact block we were already syncing!\n"); 4467 return; 4468 } 4469 } 4470 4471 PartiallyDownloadedBlock& partialBlock = *(*queuedBlockIt)->partialBlock; 4472 ReadStatus status = partialBlock.InitData(cmpctblock, vExtraTxnForCompact); 4473 if (status == READ_STATUS_INVALID) { 4474 RemoveBlockRequest(pindex->GetBlockHash(), pfrom.GetId()); // Reset in-flight state in case Misbehaving does not result in a disconnect 4475 Misbehaving(*peer, "invalid compact block"); 4476 return; 4477 } else if (status == READ_STATUS_FAILED) { 4478 if (first_in_flight) { 4479 // Duplicate txindexes, the block is now in-flight, so just request it 4480 std::vector<CInv> vInv(1); 4481 vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(*peer), blockhash); 4482 MakeAndPushMessage(pfrom, NetMsgType::GETDATA, vInv); 4483 } else { 4484 // Give up for this peer and wait for other peer(s) 4485 RemoveBlockRequest(pindex->GetBlockHash(), pfrom.GetId()); 4486 } 4487 return; 4488 } 4489 4490 BlockTransactionsRequest req; 4491 for (size_t i = 0; i < cmpctblock.BlockTxCount(); i++) { 4492 if (!partialBlock.IsTxAvailable(i)) 4493 req.indexes.push_back(i); 4494 } 4495 if (req.indexes.empty()) { 4496 fProcessBLOCKTXN = true; 4497 } else if (first_in_flight) { 4498 // We will try to round-trip any compact blocks we get on failure, 4499 // as long as it's first... 4500 req.blockhash = pindex->GetBlockHash(); 4501 MakeAndPushMessage(pfrom, NetMsgType::GETBLOCKTXN, req); 4502 } else if (pfrom.m_bip152_highbandwidth_to && 4503 (!pfrom.IsInboundConn() || 4504 IsBlockRequestedFromOutbound(blockhash) || 4505 already_in_flight < MAX_CMPCTBLOCKS_INFLIGHT_PER_BLOCK - 1)) { 4506 // ... or it's a hb relay peer and: 4507 // - peer is outbound, or 4508 // - we already have an outbound attempt in flight(so we'll take what we can get), or 4509 // - it's not the final parallel download slot (which we may reserve for first outbound) 4510 req.blockhash = pindex->GetBlockHash(); 4511 MakeAndPushMessage(pfrom, NetMsgType::GETBLOCKTXN, req); 4512 } else { 4513 // Give up for this peer and wait for other peer(s) 4514 RemoveBlockRequest(pindex->GetBlockHash(), pfrom.GetId()); 4515 } 4516 } else { 4517 // This block is either already in flight from a different 4518 // peer, or this peer has too many blocks outstanding to 4519 // download from. 4520 // Optimistically try to reconstruct anyway since we might be 4521 // able to without any round trips. 4522 PartiallyDownloadedBlock tempBlock(&m_mempool); 4523 ReadStatus status = tempBlock.InitData(cmpctblock, vExtraTxnForCompact); 4524 if (status != READ_STATUS_OK) { 4525 // TODO: don't ignore failures 4526 return; 4527 } 4528 std::vector<CTransactionRef> dummy; 4529 status = tempBlock.FillBlock(*pblock, dummy); 4530 if (status == READ_STATUS_OK) { 4531 fBlockReconstructed = true; 4532 } 4533 } 4534 } else { 4535 if (requested_block_from_this_peer) { 4536 // We requested this block, but its far into the future, so our 4537 // mempool will probably be useless - request the block normally 4538 std::vector<CInv> vInv(1); 4539 vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(*peer), blockhash); 4540 MakeAndPushMessage(pfrom, NetMsgType::GETDATA, vInv); 4541 return; 4542 } else { 4543 // If this was an announce-cmpctblock, we want the same treatment as a header message 4544 fRevertToHeaderProcessing = true; 4545 } 4546 } 4547 } // cs_main 4548 4549 if (fProcessBLOCKTXN) { 4550 BlockTransactions txn; 4551 txn.blockhash = blockhash; 4552 return ProcessCompactBlockTxns(pfrom, *peer, txn); 4553 } 4554 4555 if (fRevertToHeaderProcessing) { 4556 // Headers received from HB compact block peers are permitted to be 4557 // relayed before full validation (see BIP 152), so we don't want to disconnect 4558 // the peer if the header turns out to be for an invalid block. 4559 // Note that if a peer tries to build on an invalid chain, that 4560 // will be detected and the peer will be disconnected/discouraged. 4561 return ProcessHeadersMessage(pfrom, *peer, {cmpctblock.header}, /*via_compact_block=*/true); 4562 } 4563 4564 if (fBlockReconstructed) { 4565 // If we got here, we were able to optimistically reconstruct a 4566 // block that is in flight from some other peer. 4567 { 4568 LOCK(cs_main); 4569 mapBlockSource.emplace(pblock->GetHash(), std::make_pair(pfrom.GetId(), false)); 4570 } 4571 // Setting force_processing to true means that we bypass some of 4572 // our anti-DoS protections in AcceptBlock, which filters 4573 // unrequested blocks that might be trying to waste our resources 4574 // (eg disk space). Because we only try to reconstruct blocks when 4575 // we're close to caught up (via the CanDirectFetch() requirement 4576 // above, combined with the behavior of not requesting blocks until 4577 // we have a chain with at least the minimum chain work), and we ignore 4578 // compact blocks with less work than our tip, it is safe to treat 4579 // reconstructed compact blocks as having been requested. 4580 ProcessBlock(pfrom, pblock, /*force_processing=*/true, /*min_pow_checked=*/true); 4581 LOCK(cs_main); // hold cs_main for CBlockIndex::IsValid() 4582 if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS)) { 4583 // Clear download state for this block, which is in 4584 // process from some other peer. We do this after calling 4585 // ProcessNewBlock so that a malleated cmpctblock announcement 4586 // can't be used to interfere with block relay. 4587 RemoveBlockRequest(pblock->GetHash(), std::nullopt); 4588 } 4589 } 4590 return; 4591 } 4592 4593 if (msg_type == NetMsgType::BLOCKTXN) 4594 { 4595 // Ignore blocktxn received while importing 4596 if (m_chainman.m_blockman.LoadingBlocks()) { 4597 LogDebug(BCLog::NET, "Unexpected blocktxn message received from peer %d\n", pfrom.GetId()); 4598 return; 4599 } 4600 4601 BlockTransactions resp; 4602 vRecv >> resp; 4603 4604 return ProcessCompactBlockTxns(pfrom, *peer, resp); 4605 } 4606 4607 if (msg_type == NetMsgType::HEADERS) 4608 { 4609 // Ignore headers received while importing 4610 if (m_chainman.m_blockman.LoadingBlocks()) { 4611 LogDebug(BCLog::NET, "Unexpected headers message received from peer %d\n", pfrom.GetId()); 4612 return; 4613 } 4614 4615 std::vector<CBlockHeader> headers; 4616 4617 // Bypass the normal CBlock deserialization, as we don't want to risk deserializing 2000 full blocks. 4618 unsigned int nCount = ReadCompactSize(vRecv); 4619 if (nCount > m_opts.max_headers_result) { 4620 Misbehaving(*peer, strprintf("headers message size = %u", nCount)); 4621 return; 4622 } 4623 headers.resize(nCount); 4624 for (unsigned int n = 0; n < nCount; n++) { 4625 vRecv >> headers[n]; 4626 ReadCompactSize(vRecv); // ignore tx count; assume it is 0. 4627 } 4628 4629 ProcessHeadersMessage(pfrom, *peer, std::move(headers), /*via_compact_block=*/false); 4630 4631 // Check if the headers presync progress needs to be reported to validation. 4632 // This needs to be done without holding the m_headers_presync_mutex lock. 4633 if (m_headers_presync_should_signal.exchange(false)) { 4634 HeadersPresyncStats stats; 4635 { 4636 LOCK(m_headers_presync_mutex); 4637 auto it = m_headers_presync_stats.find(m_headers_presync_bestpeer); 4638 if (it != m_headers_presync_stats.end()) stats = it->second; 4639 } 4640 if (stats.second) { 4641 m_chainman.ReportHeadersPresync(stats.first, stats.second->first, stats.second->second); 4642 } 4643 } 4644 4645 return; 4646 } 4647 4648 if (msg_type == NetMsgType::BLOCK) 4649 { 4650 // Ignore block received while importing 4651 if (m_chainman.m_blockman.LoadingBlocks()) { 4652 LogDebug(BCLog::NET, "Unexpected block message received from peer %d\n", pfrom.GetId()); 4653 return; 4654 } 4655 4656 std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); 4657 vRecv >> TX_WITH_WITNESS(*pblock); 4658 4659 LogDebug(BCLog::NET, "received block %s peer=%d\n", pblock->GetHash().ToString(), pfrom.GetId()); 4660 4661 const CBlockIndex* prev_block{WITH_LOCK(m_chainman.GetMutex(), return m_chainman.m_blockman.LookupBlockIndex(pblock->hashPrevBlock))}; 4662 4663 // Check for possible mutation if it connects to something we know so we can check for DEPLOYMENT_SEGWIT being active 4664 if (prev_block && IsBlockMutated(/*block=*/*pblock, 4665 /*check_witness_root=*/DeploymentActiveAfter(prev_block, m_chainman, Consensus::DEPLOYMENT_SEGWIT))) { 4666 LogDebug(BCLog::NET, "Received mutated block from peer=%d\n", peer->m_id); 4667 Misbehaving(*peer, "mutated block"); 4668 WITH_LOCK(cs_main, RemoveBlockRequest(pblock->GetHash(), peer->m_id)); 4669 return; 4670 } 4671 4672 bool forceProcessing = false; 4673 const uint256 hash(pblock->GetHash()); 4674 bool min_pow_checked = false; 4675 { 4676 LOCK(cs_main); 4677 // Always process the block if we requested it, since we may 4678 // need it even when it's not a candidate for a new best tip. 4679 forceProcessing = IsBlockRequested(hash); 4680 RemoveBlockRequest(hash, pfrom.GetId()); 4681 // mapBlockSource is only used for punishing peers and setting 4682 // which peers send us compact blocks, so the race between here and 4683 // cs_main in ProcessNewBlock is fine. 4684 mapBlockSource.emplace(hash, std::make_pair(pfrom.GetId(), true)); 4685 4686 // Check claimed work on this block against our anti-dos thresholds. 4687 if (prev_block && prev_block->nChainWork + CalculateClaimedHeadersWork({{pblock->GetBlockHeader()}}) >= GetAntiDoSWorkThreshold()) { 4688 min_pow_checked = true; 4689 } 4690 } 4691 ProcessBlock(pfrom, pblock, forceProcessing, min_pow_checked); 4692 return; 4693 } 4694 4695 if (msg_type == NetMsgType::GETADDR) { 4696 // This asymmetric behavior for inbound and outbound connections was introduced 4697 // to prevent a fingerprinting attack: an attacker can send specific fake addresses 4698 // to users' AddrMan and later request them by sending getaddr messages. 4699 // Making nodes which are behind NAT and can only make outgoing connections ignore 4700 // the getaddr message mitigates the attack. 4701 if (!pfrom.IsInboundConn()) { 4702 LogDebug(BCLog::NET, "Ignoring \"getaddr\" from %s connection. peer=%d\n", pfrom.ConnectionTypeAsString(), pfrom.GetId()); 4703 return; 4704 } 4705 4706 // Since this must be an inbound connection, SetupAddressRelay will 4707 // never fail. 4708 Assume(SetupAddressRelay(pfrom, *peer)); 4709 4710 // Only send one GetAddr response per connection to reduce resource waste 4711 // and discourage addr stamping of INV announcements. 4712 if (peer->m_getaddr_recvd) { 4713 LogDebug(BCLog::NET, "Ignoring repeated \"getaddr\". peer=%d\n", pfrom.GetId()); 4714 return; 4715 } 4716 peer->m_getaddr_recvd = true; 4717 4718 peer->m_addrs_to_send.clear(); 4719 std::vector<CAddress> vAddr; 4720 if (pfrom.HasPermission(NetPermissionFlags::Addr)) { 4721 vAddr = m_connman.GetAddresses(MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND, /*network=*/std::nullopt); 4722 } else { 4723 vAddr = m_connman.GetAddresses(pfrom, MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND); 4724 } 4725 for (const CAddress &addr : vAddr) { 4726 PushAddress(*peer, addr); 4727 } 4728 return; 4729 } 4730 4731 if (msg_type == NetMsgType::MEMPOOL) { 4732 // Only process received mempool messages if we advertise NODE_BLOOM 4733 // or if the peer has mempool permissions. 4734 if (!(peer->m_our_services & NODE_BLOOM) && !pfrom.HasPermission(NetPermissionFlags::Mempool)) 4735 { 4736 if (!pfrom.HasPermission(NetPermissionFlags::NoBan)) 4737 { 4738 LogDebug(BCLog::NET, "mempool request with bloom filters disabled, %s\n", pfrom.DisconnectMsg(fLogIPs)); 4739 pfrom.fDisconnect = true; 4740 } 4741 return; 4742 } 4743 4744 if (m_connman.OutboundTargetReached(false) && !pfrom.HasPermission(NetPermissionFlags::Mempool)) 4745 { 4746 if (!pfrom.HasPermission(NetPermissionFlags::NoBan)) 4747 { 4748 LogDebug(BCLog::NET, "mempool request with bandwidth limit reached, %s\n", pfrom.DisconnectMsg(fLogIPs)); 4749 pfrom.fDisconnect = true; 4750 } 4751 return; 4752 } 4753 4754 if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 4755 LOCK(tx_relay->m_tx_inventory_mutex); 4756 tx_relay->m_send_mempool = true; 4757 } 4758 return; 4759 } 4760 4761 if (msg_type == NetMsgType::PING) { 4762 if (pfrom.GetCommonVersion() > BIP0031_VERSION) { 4763 uint64_t nonce = 0; 4764 vRecv >> nonce; 4765 // Echo the message back with the nonce. This allows for two useful features: 4766 // 4767 // 1) A remote node can quickly check if the connection is operational 4768 // 2) Remote nodes can measure the latency of the network thread. If this node 4769 // is overloaded it won't respond to pings quickly and the remote node can 4770 // avoid sending us more work, like chain download requests. 4771 // 4772 // The nonce stops the remote getting confused between different pings: without 4773 // it, if the remote node sends a ping once per second and this node takes 5 4774 // seconds to respond to each, the 5th ping the remote sends would appear to 4775 // return very quickly. 4776 MakeAndPushMessage(pfrom, NetMsgType::PONG, nonce); 4777 } 4778 return; 4779 } 4780 4781 if (msg_type == NetMsgType::PONG) { 4782 const auto ping_end = time_received; 4783 uint64_t nonce = 0; 4784 size_t nAvail = vRecv.in_avail(); 4785 bool bPingFinished = false; 4786 std::string sProblem; 4787 4788 if (nAvail >= sizeof(nonce)) { 4789 vRecv >> nonce; 4790 4791 // Only process pong message if there is an outstanding ping (old ping without nonce should never pong) 4792 if (peer->m_ping_nonce_sent != 0) { 4793 if (nonce == peer->m_ping_nonce_sent) { 4794 // Matching pong received, this ping is no longer outstanding 4795 bPingFinished = true; 4796 const auto ping_time = ping_end - peer->m_ping_start.load(); 4797 if (ping_time.count() >= 0) { 4798 // Let connman know about this successful ping-pong 4799 pfrom.PongReceived(ping_time); 4800 } else { 4801 // This should never happen 4802 sProblem = "Timing mishap"; 4803 } 4804 } else { 4805 // Nonce mismatches are normal when pings are overlapping 4806 sProblem = "Nonce mismatch"; 4807 if (nonce == 0) { 4808 // This is most likely a bug in another implementation somewhere; cancel this ping 4809 bPingFinished = true; 4810 sProblem = "Nonce zero"; 4811 } 4812 } 4813 } else { 4814 sProblem = "Unsolicited pong without ping"; 4815 } 4816 } else { 4817 // This is most likely a bug in another implementation somewhere; cancel this ping 4818 bPingFinished = true; 4819 sProblem = "Short payload"; 4820 } 4821 4822 if (!(sProblem.empty())) { 4823 LogDebug(BCLog::NET, "pong peer=%d: %s, %x expected, %x received, %u bytes\n", 4824 pfrom.GetId(), 4825 sProblem, 4826 peer->m_ping_nonce_sent, 4827 nonce, 4828 nAvail); 4829 } 4830 if (bPingFinished) { 4831 peer->m_ping_nonce_sent = 0; 4832 } 4833 return; 4834 } 4835 4836 if (msg_type == NetMsgType::FILTERLOAD) { 4837 if (!(peer->m_our_services & NODE_BLOOM)) { 4838 LogDebug(BCLog::NET, "filterload received despite not offering bloom services, %s\n", pfrom.DisconnectMsg(fLogIPs)); 4839 pfrom.fDisconnect = true; 4840 return; 4841 } 4842 CBloomFilter filter; 4843 vRecv >> filter; 4844 4845 if (!filter.IsWithinSizeConstraints()) 4846 { 4847 // There is no excuse for sending a too-large filter 4848 Misbehaving(*peer, "too-large bloom filter"); 4849 } else if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 4850 { 4851 LOCK(tx_relay->m_bloom_filter_mutex); 4852 tx_relay->m_bloom_filter.reset(new CBloomFilter(filter)); 4853 tx_relay->m_relay_txs = true; 4854 } 4855 pfrom.m_bloom_filter_loaded = true; 4856 pfrom.m_relays_txs = true; 4857 } 4858 return; 4859 } 4860 4861 if (msg_type == NetMsgType::FILTERADD) { 4862 if (!(peer->m_our_services & NODE_BLOOM)) { 4863 LogDebug(BCLog::NET, "filteradd received despite not offering bloom services, %s\n", pfrom.DisconnectMsg(fLogIPs)); 4864 pfrom.fDisconnect = true; 4865 return; 4866 } 4867 std::vector<unsigned char> vData; 4868 vRecv >> vData; 4869 4870 // Nodes must NEVER send a data item > MAX_SCRIPT_ELEMENT_SIZE bytes (the max size for a script data object, 4871 // and thus, the maximum size any matched object can have) in a filteradd message 4872 bool bad = false; 4873 if (vData.size() > MAX_SCRIPT_ELEMENT_SIZE) { 4874 bad = true; 4875 } else if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 4876 LOCK(tx_relay->m_bloom_filter_mutex); 4877 if (tx_relay->m_bloom_filter) { 4878 tx_relay->m_bloom_filter->insert(vData); 4879 } else { 4880 bad = true; 4881 } 4882 } 4883 if (bad) { 4884 Misbehaving(*peer, "bad filteradd message"); 4885 } 4886 return; 4887 } 4888 4889 if (msg_type == NetMsgType::FILTERCLEAR) { 4890 if (!(peer->m_our_services & NODE_BLOOM)) { 4891 LogDebug(BCLog::NET, "filterclear received despite not offering bloom services, %s\n", pfrom.DisconnectMsg(fLogIPs)); 4892 pfrom.fDisconnect = true; 4893 return; 4894 } 4895 auto tx_relay = peer->GetTxRelay(); 4896 if (!tx_relay) return; 4897 4898 { 4899 LOCK(tx_relay->m_bloom_filter_mutex); 4900 tx_relay->m_bloom_filter = nullptr; 4901 tx_relay->m_relay_txs = true; 4902 } 4903 pfrom.m_bloom_filter_loaded = false; 4904 pfrom.m_relays_txs = true; 4905 return; 4906 } 4907 4908 if (msg_type == NetMsgType::FEEFILTER) { 4909 CAmount newFeeFilter = 0; 4910 vRecv >> newFeeFilter; 4911 if (MoneyRange(newFeeFilter)) { 4912 if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 4913 tx_relay->m_fee_filter_received = newFeeFilter; 4914 } 4915 LogDebug(BCLog::NET, "received: feefilter of %s from peer=%d\n", CFeeRate(newFeeFilter).ToString(), pfrom.GetId()); 4916 } 4917 return; 4918 } 4919 4920 if (msg_type == NetMsgType::GETCFILTERS) { 4921 ProcessGetCFilters(pfrom, *peer, vRecv); 4922 return; 4923 } 4924 4925 if (msg_type == NetMsgType::GETCFHEADERS) { 4926 ProcessGetCFHeaders(pfrom, *peer, vRecv); 4927 return; 4928 } 4929 4930 if (msg_type == NetMsgType::GETCFCHECKPT) { 4931 ProcessGetCFCheckPt(pfrom, *peer, vRecv); 4932 return; 4933 } 4934 4935 if (msg_type == NetMsgType::NOTFOUND) { 4936 std::vector<CInv> vInv; 4937 vRecv >> vInv; 4938 std::vector<uint256> tx_invs; 4939 if (vInv.size() <= node::MAX_PEER_TX_ANNOUNCEMENTS + MAX_BLOCKS_IN_TRANSIT_PER_PEER) { 4940 for (CInv &inv : vInv) { 4941 if (inv.IsGenTxMsg()) { 4942 tx_invs.emplace_back(inv.hash); 4943 } 4944 } 4945 } 4946 LOCK(m_tx_download_mutex); 4947 m_txdownloadman.ReceivedNotFound(pfrom.GetId(), tx_invs); 4948 return; 4949 } 4950 4951 // Ignore unknown commands for extensibility 4952 LogDebug(BCLog::NET, "Unknown command \"%s\" from peer=%d\n", SanitizeString(msg_type), pfrom.GetId()); 4953 return; 4954 } 4955 4956 bool PeerManagerImpl::MaybeDiscourageAndDisconnect(CNode& pnode, Peer& peer) 4957 { 4958 { 4959 LOCK(peer.m_misbehavior_mutex); 4960 4961 // There's nothing to do if the m_should_discourage flag isn't set 4962 if (!peer.m_should_discourage) return false; 4963 4964 peer.m_should_discourage = false; 4965 } // peer.m_misbehavior_mutex 4966 4967 if (pnode.HasPermission(NetPermissionFlags::NoBan)) { 4968 // We never disconnect or discourage peers for bad behavior if they have NetPermissionFlags::NoBan permission 4969 LogPrintf("Warning: not punishing noban peer %d!\n", peer.m_id); 4970 return false; 4971 } 4972 4973 if (pnode.IsManualConn()) { 4974 // We never disconnect or discourage manual peers for bad behavior 4975 LogPrintf("Warning: not punishing manually connected peer %d!\n", peer.m_id); 4976 return false; 4977 } 4978 4979 if (pnode.addr.IsLocal()) { 4980 // We disconnect local peers for bad behavior but don't discourage (since that would discourage 4981 // all peers on the same local address) 4982 LogDebug(BCLog::NET, "Warning: disconnecting but not discouraging %s peer %d!\n", 4983 pnode.m_inbound_onion ? "inbound onion" : "local", peer.m_id); 4984 pnode.fDisconnect = true; 4985 return true; 4986 } 4987 4988 // Normal case: Disconnect the peer and discourage all nodes sharing the address 4989 LogDebug(BCLog::NET, "Disconnecting and discouraging peer %d!\n", peer.m_id); 4990 if (m_banman) m_banman->Discourage(pnode.addr); 4991 m_connman.DisconnectNode(pnode.addr); 4992 return true; 4993 } 4994 4995 bool PeerManagerImpl::ProcessMessages(CNode* pfrom, std::atomic<bool>& interruptMsgProc) 4996 { 4997 AssertLockNotHeld(m_tx_download_mutex); 4998 AssertLockHeld(g_msgproc_mutex); 4999 5000 PeerRef peer = GetPeerRef(pfrom->GetId()); 5001 if (peer == nullptr) return false; 5002 5003 // For outbound connections, ensure that the initial VERSION message 5004 // has been sent first before processing any incoming messages 5005 if (!pfrom->IsInboundConn() && !peer->m_outbound_version_message_sent) return false; 5006 5007 { 5008 LOCK(peer->m_getdata_requests_mutex); 5009 if (!peer->m_getdata_requests.empty()) { 5010 ProcessGetData(*pfrom, *peer, interruptMsgProc); 5011 } 5012 } 5013 5014 const bool processed_orphan = ProcessOrphanTx(*peer); 5015 5016 if (pfrom->fDisconnect) 5017 return false; 5018 5019 if (processed_orphan) return true; 5020 5021 // this maintains the order of responses 5022 // and prevents m_getdata_requests to grow unbounded 5023 { 5024 LOCK(peer->m_getdata_requests_mutex); 5025 if (!peer->m_getdata_requests.empty()) return true; 5026 } 5027 5028 // Don't bother if send buffer is too full to respond anyway 5029 if (pfrom->fPauseSend) return false; 5030 5031 auto poll_result{pfrom->PollMessage()}; 5032 if (!poll_result) { 5033 // No message to process 5034 return false; 5035 } 5036 5037 CNetMessage& msg{poll_result->first}; 5038 bool fMoreWork = poll_result->second; 5039 5040 TRACEPOINT(net, inbound_message, 5041 pfrom->GetId(), 5042 pfrom->m_addr_name.c_str(), 5043 pfrom->ConnectionTypeAsString().c_str(), 5044 msg.m_type.c_str(), 5045 msg.m_recv.size(), 5046 msg.m_recv.data() 5047 ); 5048 5049 if (m_opts.capture_messages) { 5050 CaptureMessage(pfrom->addr, msg.m_type, MakeUCharSpan(msg.m_recv), /*is_incoming=*/true); 5051 } 5052 5053 try { 5054 ProcessMessage(*pfrom, msg.m_type, msg.m_recv, msg.m_time, interruptMsgProc); 5055 if (interruptMsgProc) return false; 5056 { 5057 LOCK(peer->m_getdata_requests_mutex); 5058 if (!peer->m_getdata_requests.empty()) fMoreWork = true; 5059 } 5060 // Does this peer has an orphan ready to reconsider? 5061 // (Note: we may have provided a parent for an orphan provided 5062 // by another peer that was already processed; in that case, 5063 // the extra work may not be noticed, possibly resulting in an 5064 // unnecessary 100ms delay) 5065 LOCK(m_tx_download_mutex); 5066 if (m_txdownloadman.HaveMoreWork(peer->m_id)) fMoreWork = true; 5067 } catch (const std::exception& e) { 5068 LogDebug(BCLog::NET, "%s(%s, %u bytes): Exception '%s' (%s) caught\n", __func__, SanitizeString(msg.m_type), msg.m_message_size, e.what(), typeid(e).name()); 5069 } catch (...) { 5070 LogDebug(BCLog::NET, "%s(%s, %u bytes): Unknown exception caught\n", __func__, SanitizeString(msg.m_type), msg.m_message_size); 5071 } 5072 5073 return fMoreWork; 5074 } 5075 5076 void PeerManagerImpl::ConsiderEviction(CNode& pto, Peer& peer, std::chrono::seconds time_in_seconds) 5077 { 5078 AssertLockHeld(cs_main); 5079 5080 CNodeState &state = *State(pto.GetId()); 5081 5082 if (!state.m_chain_sync.m_protect && pto.IsOutboundOrBlockRelayConn() && state.fSyncStarted) { 5083 // This is an outbound peer subject to disconnection if they don't 5084 // announce a block with as much work as the current tip within 5085 // CHAIN_SYNC_TIMEOUT + HEADERS_RESPONSE_TIME seconds (note: if 5086 // their chain has more work than ours, we should sync to it, 5087 // unless it's invalid, in which case we should find that out and 5088 // disconnect from them elsewhere). 5089 if (state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= m_chainman.ActiveChain().Tip()->nChainWork) { 5090 // The outbound peer has sent us a block with at least as much work as our current tip, so reset the timeout if it was set 5091 if (state.m_chain_sync.m_timeout != 0s) { 5092 state.m_chain_sync.m_timeout = 0s; 5093 state.m_chain_sync.m_work_header = nullptr; 5094 state.m_chain_sync.m_sent_getheaders = false; 5095 } 5096 } else if (state.m_chain_sync.m_timeout == 0s || (state.m_chain_sync.m_work_header != nullptr && state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= state.m_chain_sync.m_work_header->nChainWork)) { 5097 // At this point we know that the outbound peer has either never sent us a block/header or they have, but its tip is behind ours 5098 // AND 5099 // we are noticing this for the first time (m_timeout is 0) 5100 // OR we noticed this at some point within the last CHAIN_SYNC_TIMEOUT + HEADERS_RESPONSE_TIME seconds and set a timeout 5101 // for them, they caught up to our tip at the time of setting the timer but not to our current one (we've also advanced). 5102 // Either way, set a new timeout based on our current tip. 5103 state.m_chain_sync.m_timeout = time_in_seconds + CHAIN_SYNC_TIMEOUT; 5104 state.m_chain_sync.m_work_header = m_chainman.ActiveChain().Tip(); 5105 state.m_chain_sync.m_sent_getheaders = false; 5106 } else if (state.m_chain_sync.m_timeout > 0s && time_in_seconds > state.m_chain_sync.m_timeout) { 5107 // No evidence yet that our peer has synced to a chain with work equal to that 5108 // of our tip, when we first detected it was behind. Send a single getheaders 5109 // message to give the peer a chance to update us. 5110 if (state.m_chain_sync.m_sent_getheaders) { 5111 // They've run out of time to catch up! 5112 LogInfo("Outbound peer has old chain, best known block = %s, %s\n", state.pindexBestKnownBlock != nullptr ? state.pindexBestKnownBlock->GetBlockHash().ToString() : "<none>", pto.DisconnectMsg(fLogIPs)); 5113 pto.fDisconnect = true; 5114 } else { 5115 assert(state.m_chain_sync.m_work_header); 5116 // Here, we assume that the getheaders message goes out, 5117 // because it'll either go out or be skipped because of a 5118 // getheaders in-flight already, in which case the peer should 5119 // still respond to us with a sufficiently high work chain tip. 5120 MaybeSendGetHeaders(pto, 5121 GetLocator(state.m_chain_sync.m_work_header->pprev), 5122 peer); 5123 LogDebug(BCLog::NET, "sending getheaders to outbound peer=%d to verify chain work (current best known block:%s, benchmark blockhash: %s)\n", pto.GetId(), state.pindexBestKnownBlock != nullptr ? state.pindexBestKnownBlock->GetBlockHash().ToString() : "<none>", state.m_chain_sync.m_work_header->GetBlockHash().ToString()); 5124 state.m_chain_sync.m_sent_getheaders = true; 5125 // Bump the timeout to allow a response, which could clear the timeout 5126 // (if the response shows the peer has synced), reset the timeout (if 5127 // the peer syncs to the required work but not to our tip), or result 5128 // in disconnect (if we advance to the timeout and pindexBestKnownBlock 5129 // has not sufficiently progressed) 5130 state.m_chain_sync.m_timeout = time_in_seconds + HEADERS_RESPONSE_TIME; 5131 } 5132 } 5133 } 5134 } 5135 5136 void PeerManagerImpl::EvictExtraOutboundPeers(std::chrono::seconds now) 5137 { 5138 // If we have any extra block-relay-only peers, disconnect the youngest unless 5139 // it's given us a block -- in which case, compare with the second-youngest, and 5140 // out of those two, disconnect the peer who least recently gave us a block. 5141 // The youngest block-relay-only peer would be the extra peer we connected 5142 // to temporarily in order to sync our tip; see net.cpp. 5143 // Note that we use higher nodeid as a measure for most recent connection. 5144 if (m_connman.GetExtraBlockRelayCount() > 0) { 5145 std::pair<NodeId, std::chrono::seconds> youngest_peer{-1, 0}, next_youngest_peer{-1, 0}; 5146 5147 m_connman.ForEachNode([&](CNode* pnode) { 5148 if (!pnode->IsBlockOnlyConn() || pnode->fDisconnect) return; 5149 if (pnode->GetId() > youngest_peer.first) { 5150 next_youngest_peer = youngest_peer; 5151 youngest_peer.first = pnode->GetId(); 5152 youngest_peer.second = pnode->m_last_block_time; 5153 } 5154 }); 5155 NodeId to_disconnect = youngest_peer.first; 5156 if (youngest_peer.second > next_youngest_peer.second) { 5157 // Our newest block-relay-only peer gave us a block more recently; 5158 // disconnect our second youngest. 5159 to_disconnect = next_youngest_peer.first; 5160 } 5161 m_connman.ForNode(to_disconnect, [&](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) { 5162 AssertLockHeld(::cs_main); 5163 // Make sure we're not getting a block right now, and that 5164 // we've been connected long enough for this eviction to happen 5165 // at all. 5166 // Note that we only request blocks from a peer if we learn of a 5167 // valid headers chain with at least as much work as our tip. 5168 CNodeState *node_state = State(pnode->GetId()); 5169 if (node_state == nullptr || 5170 (now - pnode->m_connected >= MINIMUM_CONNECT_TIME && node_state->vBlocksInFlight.empty())) { 5171 pnode->fDisconnect = true; 5172 LogDebug(BCLog::NET, "disconnecting extra block-relay-only peer=%d (last block received at time %d)\n", 5173 pnode->GetId(), count_seconds(pnode->m_last_block_time)); 5174 return true; 5175 } else { 5176 LogDebug(BCLog::NET, "keeping block-relay-only peer=%d chosen for eviction (connect time: %d, blocks_in_flight: %d)\n", 5177 pnode->GetId(), count_seconds(pnode->m_connected), node_state->vBlocksInFlight.size()); 5178 } 5179 return false; 5180 }); 5181 } 5182 5183 // Check whether we have too many outbound-full-relay peers 5184 if (m_connman.GetExtraFullOutboundCount() > 0) { 5185 // If we have more outbound-full-relay peers than we target, disconnect one. 5186 // Pick the outbound-full-relay peer that least recently announced 5187 // us a new block, with ties broken by choosing the more recent 5188 // connection (higher node id) 5189 // Protect peers from eviction if we don't have another connection 5190 // to their network, counting both outbound-full-relay and manual peers. 5191 NodeId worst_peer = -1; 5192 int64_t oldest_block_announcement = std::numeric_limits<int64_t>::max(); 5193 5194 m_connman.ForEachNode([&](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main, m_connman.GetNodesMutex()) { 5195 AssertLockHeld(::cs_main); 5196 5197 // Only consider outbound-full-relay peers that are not already 5198 // marked for disconnection 5199 if (!pnode->IsFullOutboundConn() || pnode->fDisconnect) return; 5200 CNodeState *state = State(pnode->GetId()); 5201 if (state == nullptr) return; // shouldn't be possible, but just in case 5202 // Don't evict our protected peers 5203 if (state->m_chain_sync.m_protect) return; 5204 // If this is the only connection on a particular network that is 5205 // OUTBOUND_FULL_RELAY or MANUAL, protect it. 5206 if (!m_connman.MultipleManualOrFullOutboundConns(pnode->addr.GetNetwork())) return; 5207 if (state->m_last_block_announcement < oldest_block_announcement || (state->m_last_block_announcement == oldest_block_announcement && pnode->GetId() > worst_peer)) { 5208 worst_peer = pnode->GetId(); 5209 oldest_block_announcement = state->m_last_block_announcement; 5210 } 5211 }); 5212 if (worst_peer != -1) { 5213 bool disconnected = m_connman.ForNode(worst_peer, [&](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) { 5214 AssertLockHeld(::cs_main); 5215 5216 // Only disconnect a peer that has been connected to us for 5217 // some reasonable fraction of our check-frequency, to give 5218 // it time for new information to have arrived. 5219 // Also don't disconnect any peer we're trying to download a 5220 // block from. 5221 CNodeState &state = *State(pnode->GetId()); 5222 if (now - pnode->m_connected > MINIMUM_CONNECT_TIME && state.vBlocksInFlight.empty()) { 5223 LogDebug(BCLog::NET, "disconnecting extra outbound peer=%d (last block announcement received at time %d)\n", pnode->GetId(), oldest_block_announcement); 5224 pnode->fDisconnect = true; 5225 return true; 5226 } else { 5227 LogDebug(BCLog::NET, "keeping outbound peer=%d chosen for eviction (connect time: %d, blocks_in_flight: %d)\n", 5228 pnode->GetId(), count_seconds(pnode->m_connected), state.vBlocksInFlight.size()); 5229 return false; 5230 } 5231 }); 5232 if (disconnected) { 5233 // If we disconnected an extra peer, that means we successfully 5234 // connected to at least one peer after the last time we 5235 // detected a stale tip. Don't try any more extra peers until 5236 // we next detect a stale tip, to limit the load we put on the 5237 // network from these extra connections. 5238 m_connman.SetTryNewOutboundPeer(false); 5239 } 5240 } 5241 } 5242 } 5243 5244 void PeerManagerImpl::CheckForStaleTipAndEvictPeers() 5245 { 5246 LOCK(cs_main); 5247 5248 auto now{GetTime<std::chrono::seconds>()}; 5249 5250 EvictExtraOutboundPeers(now); 5251 5252 if (now > m_stale_tip_check_time) { 5253 // Check whether our tip is stale, and if so, allow using an extra 5254 // outbound peer 5255 if (!m_chainman.m_blockman.LoadingBlocks() && m_connman.GetNetworkActive() && m_connman.GetUseAddrmanOutgoing() && TipMayBeStale()) { 5256 LogPrintf("Potential stale tip detected, will try using extra outbound peer (last tip update: %d seconds ago)\n", 5257 count_seconds(now - m_last_tip_update.load())); 5258 m_connman.SetTryNewOutboundPeer(true); 5259 } else if (m_connman.GetTryNewOutboundPeer()) { 5260 m_connman.SetTryNewOutboundPeer(false); 5261 } 5262 m_stale_tip_check_time = now + STALE_CHECK_INTERVAL; 5263 } 5264 5265 if (!m_initial_sync_finished && CanDirectFetch()) { 5266 m_connman.StartExtraBlockRelayPeers(); 5267 m_initial_sync_finished = true; 5268 } 5269 } 5270 5271 void PeerManagerImpl::MaybeSendPing(CNode& node_to, Peer& peer, std::chrono::microseconds now) 5272 { 5273 if (m_connman.ShouldRunInactivityChecks(node_to, std::chrono::duration_cast<std::chrono::seconds>(now)) && 5274 peer.m_ping_nonce_sent && 5275 now > peer.m_ping_start.load() + TIMEOUT_INTERVAL) 5276 { 5277 // The ping timeout is using mocktime. To disable the check during 5278 // testing, increase -peertimeout. 5279 LogDebug(BCLog::NET, "ping timeout: %fs, %s", 0.000001 * count_microseconds(now - peer.m_ping_start.load()), node_to.DisconnectMsg(fLogIPs)); 5280 node_to.fDisconnect = true; 5281 return; 5282 } 5283 5284 bool pingSend = false; 5285 5286 if (peer.m_ping_queued) { 5287 // RPC ping request by user 5288 pingSend = true; 5289 } 5290 5291 if (peer.m_ping_nonce_sent == 0 && now > peer.m_ping_start.load() + PING_INTERVAL) { 5292 // Ping automatically sent as a latency probe & keepalive. 5293 pingSend = true; 5294 } 5295 5296 if (pingSend) { 5297 uint64_t nonce; 5298 do { 5299 nonce = FastRandomContext().rand64(); 5300 } while (nonce == 0); 5301 peer.m_ping_queued = false; 5302 peer.m_ping_start = now; 5303 if (node_to.GetCommonVersion() > BIP0031_VERSION) { 5304 peer.m_ping_nonce_sent = nonce; 5305 MakeAndPushMessage(node_to, NetMsgType::PING, nonce); 5306 } else { 5307 // Peer is too old to support ping command with nonce, pong will never arrive. 5308 peer.m_ping_nonce_sent = 0; 5309 MakeAndPushMessage(node_to, NetMsgType::PING); 5310 } 5311 } 5312 } 5313 5314 void PeerManagerImpl::MaybeSendAddr(CNode& node, Peer& peer, std::chrono::microseconds current_time) 5315 { 5316 // Nothing to do for non-address-relay peers 5317 if (!peer.m_addr_relay_enabled) return; 5318 5319 LOCK(peer.m_addr_send_times_mutex); 5320 // Periodically advertise our local address to the peer. 5321 if (fListen && !m_chainman.IsInitialBlockDownload() && 5322 peer.m_next_local_addr_send < current_time) { 5323 // If we've sent before, clear the bloom filter for the peer, so that our 5324 // self-announcement will actually go out. 5325 // This might be unnecessary if the bloom filter has already rolled 5326 // over since our last self-announcement, but there is only a small 5327 // bandwidth cost that we can incur by doing this (which happens 5328 // once a day on average). 5329 if (peer.m_next_local_addr_send != 0us) { 5330 peer.m_addr_known->reset(); 5331 } 5332 if (std::optional<CService> local_service = GetLocalAddrForPeer(node)) { 5333 CAddress local_addr{*local_service, peer.m_our_services, Now<NodeSeconds>()}; 5334 PushAddress(peer, local_addr); 5335 } 5336 peer.m_next_local_addr_send = current_time + m_rng.rand_exp_duration(AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL); 5337 } 5338 5339 // We sent an `addr` message to this peer recently. Nothing more to do. 5340 if (current_time <= peer.m_next_addr_send) return; 5341 5342 peer.m_next_addr_send = current_time + m_rng.rand_exp_duration(AVG_ADDRESS_BROADCAST_INTERVAL); 5343 5344 if (!Assume(peer.m_addrs_to_send.size() <= MAX_ADDR_TO_SEND)) { 5345 // Should be impossible since we always check size before adding to 5346 // m_addrs_to_send. Recover by trimming the vector. 5347 peer.m_addrs_to_send.resize(MAX_ADDR_TO_SEND); 5348 } 5349 5350 // Remove addr records that the peer already knows about, and add new 5351 // addrs to the m_addr_known filter on the same pass. 5352 auto addr_already_known = [&peer](const CAddress& addr) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex) { 5353 bool ret = peer.m_addr_known->contains(addr.GetKey()); 5354 if (!ret) peer.m_addr_known->insert(addr.GetKey()); 5355 return ret; 5356 }; 5357 peer.m_addrs_to_send.erase(std::remove_if(peer.m_addrs_to_send.begin(), peer.m_addrs_to_send.end(), addr_already_known), 5358 peer.m_addrs_to_send.end()); 5359 5360 // No addr messages to send 5361 if (peer.m_addrs_to_send.empty()) return; 5362 5363 if (peer.m_wants_addrv2) { 5364 MakeAndPushMessage(node, NetMsgType::ADDRV2, CAddress::V2_NETWORK(peer.m_addrs_to_send)); 5365 } else { 5366 MakeAndPushMessage(node, NetMsgType::ADDR, CAddress::V1_NETWORK(peer.m_addrs_to_send)); 5367 } 5368 peer.m_addrs_to_send.clear(); 5369 5370 // we only send the big addr message once 5371 if (peer.m_addrs_to_send.capacity() > 40) { 5372 peer.m_addrs_to_send.shrink_to_fit(); 5373 } 5374 } 5375 5376 void PeerManagerImpl::MaybeSendSendHeaders(CNode& node, Peer& peer) 5377 { 5378 // Delay sending SENDHEADERS (BIP 130) until we're done with an 5379 // initial-headers-sync with this peer. Receiving headers announcements for 5380 // new blocks while trying to sync their headers chain is problematic, 5381 // because of the state tracking done. 5382 if (!peer.m_sent_sendheaders && node.GetCommonVersion() >= SENDHEADERS_VERSION) { 5383 LOCK(cs_main); 5384 CNodeState &state = *State(node.GetId()); 5385 if (state.pindexBestKnownBlock != nullptr && 5386 state.pindexBestKnownBlock->nChainWork > m_chainman.MinimumChainWork()) { 5387 // Tell our peer we prefer to receive headers rather than inv's 5388 // We send this to non-NODE NETWORK peers as well, because even 5389 // non-NODE NETWORK peers can announce blocks (such as pruning 5390 // nodes) 5391 MakeAndPushMessage(node, NetMsgType::SENDHEADERS); 5392 peer.m_sent_sendheaders = true; 5393 } 5394 } 5395 } 5396 5397 void PeerManagerImpl::MaybeSendFeefilter(CNode& pto, Peer& peer, std::chrono::microseconds current_time) 5398 { 5399 if (m_opts.ignore_incoming_txs) return; 5400 if (pto.GetCommonVersion() < FEEFILTER_VERSION) return; 5401 // peers with the forcerelay permission should not filter txs to us 5402 if (pto.HasPermission(NetPermissionFlags::ForceRelay)) return; 5403 // Don't send feefilter messages to outbound block-relay-only peers since they should never announce 5404 // transactions to us, regardless of feefilter state. 5405 if (pto.IsBlockOnlyConn()) return; 5406 5407 CAmount currentFilter = m_mempool.GetMinFee().GetFeePerK(); 5408 5409 if (m_chainman.IsInitialBlockDownload()) { 5410 // Received tx-inv messages are discarded when the active 5411 // chainstate is in IBD, so tell the peer to not send them. 5412 currentFilter = MAX_MONEY; 5413 } else { 5414 static const CAmount MAX_FILTER{m_fee_filter_rounder.round(MAX_MONEY)}; 5415 if (peer.m_fee_filter_sent == MAX_FILTER) { 5416 // Send the current filter if we sent MAX_FILTER previously 5417 // and made it out of IBD. 5418 peer.m_next_send_feefilter = 0us; 5419 } 5420 } 5421 if (current_time > peer.m_next_send_feefilter) { 5422 CAmount filterToSend = m_fee_filter_rounder.round(currentFilter); 5423 // We always have a fee filter of at least the min relay fee 5424 filterToSend = std::max(filterToSend, m_mempool.m_opts.min_relay_feerate.GetFeePerK()); 5425 if (filterToSend != peer.m_fee_filter_sent) { 5426 MakeAndPushMessage(pto, NetMsgType::FEEFILTER, filterToSend); 5427 peer.m_fee_filter_sent = filterToSend; 5428 } 5429 peer.m_next_send_feefilter = current_time + m_rng.rand_exp_duration(AVG_FEEFILTER_BROADCAST_INTERVAL); 5430 } 5431 // If the fee filter has changed substantially and it's still more than MAX_FEEFILTER_CHANGE_DELAY 5432 // until scheduled broadcast, then move the broadcast to within MAX_FEEFILTER_CHANGE_DELAY. 5433 else if (current_time + MAX_FEEFILTER_CHANGE_DELAY < peer.m_next_send_feefilter && 5434 (currentFilter < 3 * peer.m_fee_filter_sent / 4 || currentFilter > 4 * peer.m_fee_filter_sent / 3)) { 5435 peer.m_next_send_feefilter = current_time + m_rng.randrange<std::chrono::microseconds>(MAX_FEEFILTER_CHANGE_DELAY); 5436 } 5437 } 5438 5439 namespace { 5440 class CompareInvMempoolOrder 5441 { 5442 CTxMemPool* mp; 5443 bool m_wtxid_relay; 5444 public: 5445 explicit CompareInvMempoolOrder(CTxMemPool *_mempool, bool use_wtxid) 5446 { 5447 mp = _mempool; 5448 m_wtxid_relay = use_wtxid; 5449 } 5450 5451 bool operator()(std::set<uint256>::iterator a, std::set<uint256>::iterator b) 5452 { 5453 /* As std::make_heap produces a max-heap, we want the entries with the 5454 * fewest ancestors/highest fee to sort later. */ 5455 return mp->CompareDepthAndScore(*b, *a, m_wtxid_relay); 5456 } 5457 }; 5458 } // namespace 5459 5460 bool PeerManagerImpl::RejectIncomingTxs(const CNode& peer) const 5461 { 5462 // block-relay-only peers may never send txs to us 5463 if (peer.IsBlockOnlyConn()) return true; 5464 if (peer.IsFeelerConn()) return true; 5465 // In -blocksonly mode, peers need the 'relay' permission to send txs to us 5466 if (m_opts.ignore_incoming_txs && !peer.HasPermission(NetPermissionFlags::Relay)) return true; 5467 return false; 5468 } 5469 5470 bool PeerManagerImpl::SetupAddressRelay(const CNode& node, Peer& peer) 5471 { 5472 // We don't participate in addr relay with outbound block-relay-only 5473 // connections to prevent providing adversaries with the additional 5474 // information of addr traffic to infer the link. 5475 if (node.IsBlockOnlyConn()) return false; 5476 5477 if (!peer.m_addr_relay_enabled.exchange(true)) { 5478 // During version message processing (non-block-relay-only outbound peers) 5479 // or on first addr-related message we have received (inbound peers), initialize 5480 // m_addr_known. 5481 peer.m_addr_known = std::make_unique<CRollingBloomFilter>(5000, 0.001); 5482 } 5483 5484 return true; 5485 } 5486 5487 bool PeerManagerImpl::SendMessages(CNode* pto) 5488 { 5489 AssertLockNotHeld(m_tx_download_mutex); 5490 AssertLockHeld(g_msgproc_mutex); 5491 5492 PeerRef peer = GetPeerRef(pto->GetId()); 5493 if (!peer) return false; 5494 const Consensus::Params& consensusParams = m_chainparams.GetConsensus(); 5495 5496 // We must call MaybeDiscourageAndDisconnect first, to ensure that we'll 5497 // disconnect misbehaving peers even before the version handshake is complete. 5498 if (MaybeDiscourageAndDisconnect(*pto, *peer)) return true; 5499 5500 // Initiate version handshake for outbound connections 5501 if (!pto->IsInboundConn() && !peer->m_outbound_version_message_sent) { 5502 PushNodeVersion(*pto, *peer); 5503 peer->m_outbound_version_message_sent = true; 5504 } 5505 5506 // Don't send anything until the version handshake is complete 5507 if (!pto->fSuccessfullyConnected || pto->fDisconnect) 5508 return true; 5509 5510 const auto current_time{GetTime<std::chrono::microseconds>()}; 5511 5512 if (pto->IsAddrFetchConn() && current_time - pto->m_connected > 10 * AVG_ADDRESS_BROADCAST_INTERVAL) { 5513 LogDebug(BCLog::NET, "addrfetch connection timeout, %s\n", pto->DisconnectMsg(fLogIPs)); 5514 pto->fDisconnect = true; 5515 return true; 5516 } 5517 5518 MaybeSendPing(*pto, *peer, current_time); 5519 5520 // MaybeSendPing may have marked peer for disconnection 5521 if (pto->fDisconnect) return true; 5522 5523 MaybeSendAddr(*pto, *peer, current_time); 5524 5525 MaybeSendSendHeaders(*pto, *peer); 5526 5527 { 5528 LOCK(cs_main); 5529 5530 CNodeState &state = *State(pto->GetId()); 5531 5532 // Start block sync 5533 if (m_chainman.m_best_header == nullptr) { 5534 m_chainman.m_best_header = m_chainman.ActiveChain().Tip(); 5535 } 5536 5537 // Determine whether we might try initial headers sync or parallel 5538 // block download from this peer -- this mostly affects behavior while 5539 // in IBD (once out of IBD, we sync from all peers). 5540 bool sync_blocks_and_headers_from_peer = false; 5541 if (state.fPreferredDownload) { 5542 sync_blocks_and_headers_from_peer = true; 5543 } else if (CanServeBlocks(*peer) && !pto->IsAddrFetchConn()) { 5544 // Typically this is an inbound peer. If we don't have any outbound 5545 // peers, or if we aren't downloading any blocks from such peers, 5546 // then allow block downloads from this peer, too. 5547 // We prefer downloading blocks from outbound peers to avoid 5548 // putting undue load on (say) some home user who is just making 5549 // outbound connections to the network, but if our only source of 5550 // the latest blocks is from an inbound peer, we have to be sure to 5551 // eventually download it (and not just wait indefinitely for an 5552 // outbound peer to have it). 5553 if (m_num_preferred_download_peers == 0 || mapBlocksInFlight.empty()) { 5554 sync_blocks_and_headers_from_peer = true; 5555 } 5556 } 5557 5558 if (!state.fSyncStarted && CanServeBlocks(*peer) && !m_chainman.m_blockman.LoadingBlocks()) { 5559 // Only actively request headers from a single peer, unless we're close to today. 5560 if ((nSyncStarted == 0 && sync_blocks_and_headers_from_peer) || m_chainman.m_best_header->Time() > NodeClock::now() - 24h) { 5561 const CBlockIndex* pindexStart = m_chainman.m_best_header; 5562 /* If possible, start at the block preceding the currently 5563 best known header. This ensures that we always get a 5564 non-empty list of headers back as long as the peer 5565 is up-to-date. With a non-empty response, we can initialise 5566 the peer's known best block. This wouldn't be possible 5567 if we requested starting at m_chainman.m_best_header and 5568 got back an empty response. */ 5569 if (pindexStart->pprev) 5570 pindexStart = pindexStart->pprev; 5571 if (MaybeSendGetHeaders(*pto, GetLocator(pindexStart), *peer)) { 5572 LogDebug(BCLog::NET, "initial getheaders (%d) to peer=%d (startheight:%d)\n", pindexStart->nHeight, pto->GetId(), peer->m_starting_height); 5573 5574 state.fSyncStarted = true; 5575 peer->m_headers_sync_timeout = current_time + HEADERS_DOWNLOAD_TIMEOUT_BASE + 5576 ( 5577 // Convert HEADERS_DOWNLOAD_TIMEOUT_PER_HEADER to microseconds before scaling 5578 // to maintain precision 5579 std::chrono::microseconds{HEADERS_DOWNLOAD_TIMEOUT_PER_HEADER} * 5580 Ticks<std::chrono::seconds>(NodeClock::now() - m_chainman.m_best_header->Time()) / consensusParams.nPowTargetSpacing 5581 ); 5582 nSyncStarted++; 5583 } 5584 } 5585 } 5586 5587 // 5588 // Try sending block announcements via headers 5589 // 5590 { 5591 // If we have no more than MAX_BLOCKS_TO_ANNOUNCE in our 5592 // list of block hashes we're relaying, and our peer wants 5593 // headers announcements, then find the first header 5594 // not yet known to our peer but would connect, and send. 5595 // If no header would connect, or if we have too many 5596 // blocks, or if the peer doesn't want headers, just 5597 // add all to the inv queue. 5598 LOCK(peer->m_block_inv_mutex); 5599 std::vector<CBlock> vHeaders; 5600 bool fRevertToInv = ((!peer->m_prefers_headers && 5601 (!state.m_requested_hb_cmpctblocks || peer->m_blocks_for_headers_relay.size() > 1)) || 5602 peer->m_blocks_for_headers_relay.size() > MAX_BLOCKS_TO_ANNOUNCE); 5603 const CBlockIndex *pBestIndex = nullptr; // last header queued for delivery 5604 ProcessBlockAvailability(pto->GetId()); // ensure pindexBestKnownBlock is up-to-date 5605 5606 if (!fRevertToInv) { 5607 bool fFoundStartingHeader = false; 5608 // Try to find first header that our peer doesn't have, and 5609 // then send all headers past that one. If we come across any 5610 // headers that aren't on m_chainman.ActiveChain(), give up. 5611 for (const uint256& hash : peer->m_blocks_for_headers_relay) { 5612 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(hash); 5613 assert(pindex); 5614 if (m_chainman.ActiveChain()[pindex->nHeight] != pindex) { 5615 // Bail out if we reorged away from this block 5616 fRevertToInv = true; 5617 break; 5618 } 5619 if (pBestIndex != nullptr && pindex->pprev != pBestIndex) { 5620 // This means that the list of blocks to announce don't 5621 // connect to each other. 5622 // This shouldn't really be possible to hit during 5623 // regular operation (because reorgs should take us to 5624 // a chain that has some block not on the prior chain, 5625 // which should be caught by the prior check), but one 5626 // way this could happen is by using invalidateblock / 5627 // reconsiderblock repeatedly on the tip, causing it to 5628 // be added multiple times to m_blocks_for_headers_relay. 5629 // Robustly deal with this rare situation by reverting 5630 // to an inv. 5631 fRevertToInv = true; 5632 break; 5633 } 5634 pBestIndex = pindex; 5635 if (fFoundStartingHeader) { 5636 // add this to the headers message 5637 vHeaders.emplace_back(pindex->GetBlockHeader()); 5638 } else if (PeerHasHeader(&state, pindex)) { 5639 continue; // keep looking for the first new block 5640 } else if (pindex->pprev == nullptr || PeerHasHeader(&state, pindex->pprev)) { 5641 // Peer doesn't have this header but they do have the prior one. 5642 // Start sending headers. 5643 fFoundStartingHeader = true; 5644 vHeaders.emplace_back(pindex->GetBlockHeader()); 5645 } else { 5646 // Peer doesn't have this header or the prior one -- nothing will 5647 // connect, so bail out. 5648 fRevertToInv = true; 5649 break; 5650 } 5651 } 5652 } 5653 if (!fRevertToInv && !vHeaders.empty()) { 5654 if (vHeaders.size() == 1 && state.m_requested_hb_cmpctblocks) { 5655 // We only send up to 1 block as header-and-ids, as otherwise 5656 // probably means we're doing an initial-ish-sync or they're slow 5657 LogDebug(BCLog::NET, "%s sending header-and-ids %s to peer=%d\n", __func__, 5658 vHeaders.front().GetHash().ToString(), pto->GetId()); 5659 5660 std::optional<CSerializedNetMsg> cached_cmpctblock_msg; 5661 { 5662 LOCK(m_most_recent_block_mutex); 5663 if (m_most_recent_block_hash == pBestIndex->GetBlockHash()) { 5664 cached_cmpctblock_msg = NetMsg::Make(NetMsgType::CMPCTBLOCK, *m_most_recent_compact_block); 5665 } 5666 } 5667 if (cached_cmpctblock_msg.has_value()) { 5668 PushMessage(*pto, std::move(cached_cmpctblock_msg.value())); 5669 } else { 5670 CBlock block; 5671 const bool ret{m_chainman.m_blockman.ReadBlock(block, *pBestIndex)}; 5672 assert(ret); 5673 CBlockHeaderAndShortTxIDs cmpctblock{block, m_rng.rand64()}; 5674 MakeAndPushMessage(*pto, NetMsgType::CMPCTBLOCK, cmpctblock); 5675 } 5676 state.pindexBestHeaderSent = pBestIndex; 5677 } else if (peer->m_prefers_headers) { 5678 if (vHeaders.size() > 1) { 5679 LogDebug(BCLog::NET, "%s: %u headers, range (%s, %s), to peer=%d\n", __func__, 5680 vHeaders.size(), 5681 vHeaders.front().GetHash().ToString(), 5682 vHeaders.back().GetHash().ToString(), pto->GetId()); 5683 } else { 5684 LogDebug(BCLog::NET, "%s: sending header %s to peer=%d\n", __func__, 5685 vHeaders.front().GetHash().ToString(), pto->GetId()); 5686 } 5687 MakeAndPushMessage(*pto, NetMsgType::HEADERS, TX_WITH_WITNESS(vHeaders)); 5688 state.pindexBestHeaderSent = pBestIndex; 5689 } else 5690 fRevertToInv = true; 5691 } 5692 if (fRevertToInv) { 5693 // If falling back to using an inv, just try to inv the tip. 5694 // The last entry in m_blocks_for_headers_relay was our tip at some point 5695 // in the past. 5696 if (!peer->m_blocks_for_headers_relay.empty()) { 5697 const uint256& hashToAnnounce = peer->m_blocks_for_headers_relay.back(); 5698 const CBlockIndex* pindex = m_chainman.m_blockman.LookupBlockIndex(hashToAnnounce); 5699 assert(pindex); 5700 5701 // Warn if we're announcing a block that is not on the main chain. 5702 // This should be very rare and could be optimized out. 5703 // Just log for now. 5704 if (m_chainman.ActiveChain()[pindex->nHeight] != pindex) { 5705 LogDebug(BCLog::NET, "Announcing block %s not on main chain (tip=%s)\n", 5706 hashToAnnounce.ToString(), m_chainman.ActiveChain().Tip()->GetBlockHash().ToString()); 5707 } 5708 5709 // If the peer's chain has this block, don't inv it back. 5710 if (!PeerHasHeader(&state, pindex)) { 5711 peer->m_blocks_for_inv_relay.push_back(hashToAnnounce); 5712 LogDebug(BCLog::NET, "%s: sending inv peer=%d hash=%s\n", __func__, 5713 pto->GetId(), hashToAnnounce.ToString()); 5714 } 5715 } 5716 } 5717 peer->m_blocks_for_headers_relay.clear(); 5718 } 5719 5720 // 5721 // Message: inventory 5722 // 5723 std::vector<CInv> vInv; 5724 { 5725 LOCK(peer->m_block_inv_mutex); 5726 vInv.reserve(std::max<size_t>(peer->m_blocks_for_inv_relay.size(), INVENTORY_BROADCAST_TARGET)); 5727 5728 // Add blocks 5729 for (const uint256& hash : peer->m_blocks_for_inv_relay) { 5730 vInv.emplace_back(MSG_BLOCK, hash); 5731 if (vInv.size() == MAX_INV_SZ) { 5732 MakeAndPushMessage(*pto, NetMsgType::INV, vInv); 5733 vInv.clear(); 5734 } 5735 } 5736 peer->m_blocks_for_inv_relay.clear(); 5737 } 5738 5739 if (auto tx_relay = peer->GetTxRelay(); tx_relay != nullptr) { 5740 LOCK(tx_relay->m_tx_inventory_mutex); 5741 // Check whether periodic sends should happen 5742 bool fSendTrickle = pto->HasPermission(NetPermissionFlags::NoBan); 5743 if (tx_relay->m_next_inv_send_time < current_time) { 5744 fSendTrickle = true; 5745 if (pto->IsInboundConn()) { 5746 tx_relay->m_next_inv_send_time = NextInvToInbounds(current_time, INBOUND_INVENTORY_BROADCAST_INTERVAL); 5747 } else { 5748 tx_relay->m_next_inv_send_time = current_time + m_rng.rand_exp_duration(OUTBOUND_INVENTORY_BROADCAST_INTERVAL); 5749 } 5750 } 5751 5752 // Time to send but the peer has requested we not relay transactions. 5753 if (fSendTrickle) { 5754 LOCK(tx_relay->m_bloom_filter_mutex); 5755 if (!tx_relay->m_relay_txs) tx_relay->m_tx_inventory_to_send.clear(); 5756 } 5757 5758 // Respond to BIP35 mempool requests 5759 if (fSendTrickle && tx_relay->m_send_mempool) { 5760 auto vtxinfo = m_mempool.infoAll(); 5761 tx_relay->m_send_mempool = false; 5762 const CFeeRate filterrate{tx_relay->m_fee_filter_received.load()}; 5763 5764 LOCK(tx_relay->m_bloom_filter_mutex); 5765 5766 for (const auto& txinfo : vtxinfo) { 5767 CInv inv{ 5768 peer->m_wtxid_relay ? MSG_WTX : MSG_TX, 5769 peer->m_wtxid_relay ? 5770 txinfo.tx->GetWitnessHash().ToUint256() : 5771 txinfo.tx->GetHash().ToUint256(), 5772 }; 5773 tx_relay->m_tx_inventory_to_send.erase(inv.hash); 5774 5775 // Don't send transactions that peers will not put into their mempool 5776 if (txinfo.fee < filterrate.GetFee(txinfo.vsize)) { 5777 continue; 5778 } 5779 if (tx_relay->m_bloom_filter) { 5780 if (!tx_relay->m_bloom_filter->IsRelevantAndUpdate(*txinfo.tx)) continue; 5781 } 5782 tx_relay->m_tx_inventory_known_filter.insert(inv.hash); 5783 vInv.push_back(inv); 5784 if (vInv.size() == MAX_INV_SZ) { 5785 MakeAndPushMessage(*pto, NetMsgType::INV, vInv); 5786 vInv.clear(); 5787 } 5788 } 5789 } 5790 5791 // Determine transactions to relay 5792 if (fSendTrickle) { 5793 // Produce a vector with all candidates for sending 5794 std::vector<std::set<uint256>::iterator> vInvTx; 5795 vInvTx.reserve(tx_relay->m_tx_inventory_to_send.size()); 5796 for (std::set<uint256>::iterator it = tx_relay->m_tx_inventory_to_send.begin(); it != tx_relay->m_tx_inventory_to_send.end(); it++) { 5797 vInvTx.push_back(it); 5798 } 5799 const CFeeRate filterrate{tx_relay->m_fee_filter_received.load()}; 5800 // Topologically and fee-rate sort the inventory we send for privacy and priority reasons. 5801 // A heap is used so that not all items need sorting if only a few are being sent. 5802 CompareInvMempoolOrder compareInvMempoolOrder(&m_mempool, peer->m_wtxid_relay); 5803 std::make_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder); 5804 // No reason to drain out at many times the network's capacity, 5805 // especially since we have many peers and some will draw much shorter delays. 5806 unsigned int nRelayedTransactions = 0; 5807 LOCK(tx_relay->m_bloom_filter_mutex); 5808 size_t broadcast_max{INVENTORY_BROADCAST_TARGET + (tx_relay->m_tx_inventory_to_send.size()/1000)*5}; 5809 broadcast_max = std::min<size_t>(INVENTORY_BROADCAST_MAX, broadcast_max); 5810 while (!vInvTx.empty() && nRelayedTransactions < broadcast_max) { 5811 // Fetch the top element from the heap 5812 std::pop_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder); 5813 std::set<uint256>::iterator it = vInvTx.back(); 5814 vInvTx.pop_back(); 5815 uint256 hash = *it; 5816 CInv inv(peer->m_wtxid_relay ? MSG_WTX : MSG_TX, hash); 5817 // Remove it from the to-be-sent set 5818 tx_relay->m_tx_inventory_to_send.erase(it); 5819 // Check if not in the filter already 5820 if (tx_relay->m_tx_inventory_known_filter.contains(hash)) { 5821 continue; 5822 } 5823 // Not in the mempool anymore? don't bother sending it. 5824 auto txinfo = m_mempool.info(ToGenTxid(inv)); 5825 if (!txinfo.tx) { 5826 continue; 5827 } 5828 // Peer told you to not send transactions at that feerate? Don't bother sending it. 5829 if (txinfo.fee < filterrate.GetFee(txinfo.vsize)) { 5830 continue; 5831 } 5832 if (tx_relay->m_bloom_filter && !tx_relay->m_bloom_filter->IsRelevantAndUpdate(*txinfo.tx)) continue; 5833 // Send 5834 vInv.push_back(inv); 5835 nRelayedTransactions++; 5836 if (vInv.size() == MAX_INV_SZ) { 5837 MakeAndPushMessage(*pto, NetMsgType::INV, vInv); 5838 vInv.clear(); 5839 } 5840 tx_relay->m_tx_inventory_known_filter.insert(hash); 5841 } 5842 5843 // Ensure we'll respond to GETDATA requests for anything we've just announced 5844 LOCK(m_mempool.cs); 5845 tx_relay->m_last_inv_sequence = m_mempool.GetSequence(); 5846 } 5847 } 5848 if (!vInv.empty()) 5849 MakeAndPushMessage(*pto, NetMsgType::INV, vInv); 5850 5851 // Detect whether we're stalling 5852 auto stalling_timeout = m_block_stalling_timeout.load(); 5853 if (state.m_stalling_since.count() && state.m_stalling_since < current_time - stalling_timeout) { 5854 // Stalling only triggers when the block download window cannot move. During normal steady state, 5855 // the download window should be much larger than the to-be-downloaded set of blocks, so disconnection 5856 // should only happen during initial block download. 5857 LogInfo("Peer is stalling block download, %s\n", pto->DisconnectMsg(fLogIPs)); 5858 pto->fDisconnect = true; 5859 // Increase timeout for the next peer so that we don't disconnect multiple peers if our own 5860 // bandwidth is insufficient. 5861 const auto new_timeout = std::min(2 * stalling_timeout, BLOCK_STALLING_TIMEOUT_MAX); 5862 if (stalling_timeout != new_timeout && m_block_stalling_timeout.compare_exchange_strong(stalling_timeout, new_timeout)) { 5863 LogDebug(BCLog::NET, "Increased stalling timeout temporarily to %d seconds\n", count_seconds(new_timeout)); 5864 } 5865 return true; 5866 } 5867 // In case there is a block that has been in flight from this peer for block_interval * (1 + 0.5 * N) 5868 // (with N the number of peers from which we're downloading validated blocks), disconnect due to timeout. 5869 // We compensate for other peers to prevent killing off peers due to our own downstream link 5870 // being saturated. We only count validated in-flight blocks so peers can't advertise non-existing block hashes 5871 // to unreasonably increase our timeout. 5872 if (state.vBlocksInFlight.size() > 0) { 5873 QueuedBlock &queuedBlock = state.vBlocksInFlight.front(); 5874 int nOtherPeersWithValidatedDownloads = m_peers_downloading_from - 1; 5875 if (current_time > state.m_downloading_since + std::chrono::seconds{consensusParams.nPowTargetSpacing} * (BLOCK_DOWNLOAD_TIMEOUT_BASE + BLOCK_DOWNLOAD_TIMEOUT_PER_PEER * nOtherPeersWithValidatedDownloads)) { 5876 LogInfo("Timeout downloading block %s, %s\n", queuedBlock.pindex->GetBlockHash().ToString(), pto->DisconnectMsg(fLogIPs)); 5877 pto->fDisconnect = true; 5878 return true; 5879 } 5880 } 5881 // Check for headers sync timeouts 5882 if (state.fSyncStarted && peer->m_headers_sync_timeout < std::chrono::microseconds::max()) { 5883 // Detect whether this is a stalling initial-headers-sync peer 5884 if (m_chainman.m_best_header->Time() <= NodeClock::now() - 24h) { 5885 if (current_time > peer->m_headers_sync_timeout && nSyncStarted == 1 && (m_num_preferred_download_peers - state.fPreferredDownload >= 1)) { 5886 // Disconnect a peer (without NetPermissionFlags::NoBan permission) if it is our only sync peer, 5887 // and we have others we could be using instead. 5888 // Note: If all our peers are inbound, then we won't 5889 // disconnect our sync peer for stalling; we have bigger 5890 // problems if we can't get any outbound peers. 5891 if (!pto->HasPermission(NetPermissionFlags::NoBan)) { 5892 LogInfo("Timeout downloading headers, %s\n", pto->DisconnectMsg(fLogIPs)); 5893 pto->fDisconnect = true; 5894 return true; 5895 } else { 5896 LogInfo("Timeout downloading headers from noban peer, not %s\n", pto->DisconnectMsg(fLogIPs)); 5897 // Reset the headers sync state so that we have a 5898 // chance to try downloading from a different peer. 5899 // Note: this will also result in at least one more 5900 // getheaders message to be sent to 5901 // this peer (eventually). 5902 state.fSyncStarted = false; 5903 nSyncStarted--; 5904 peer->m_headers_sync_timeout = 0us; 5905 } 5906 } 5907 } else { 5908 // After we've caught up once, reset the timeout so we can't trigger 5909 // disconnect later. 5910 peer->m_headers_sync_timeout = std::chrono::microseconds::max(); 5911 } 5912 } 5913 5914 // Check that outbound peers have reasonable chains 5915 // GetTime() is used by this anti-DoS logic so we can test this using mocktime 5916 ConsiderEviction(*pto, *peer, GetTime<std::chrono::seconds>()); 5917 5918 // 5919 // Message: getdata (blocks) 5920 // 5921 std::vector<CInv> vGetData; 5922 if (CanServeBlocks(*peer) && ((sync_blocks_and_headers_from_peer && !IsLimitedPeer(*peer)) || !m_chainman.IsInitialBlockDownload()) && state.vBlocksInFlight.size() < MAX_BLOCKS_IN_TRANSIT_PER_PEER) { 5923 std::vector<const CBlockIndex*> vToDownload; 5924 NodeId staller = -1; 5925 auto get_inflight_budget = [&state]() { 5926 return std::max(0, MAX_BLOCKS_IN_TRANSIT_PER_PEER - static_cast<int>(state.vBlocksInFlight.size())); 5927 }; 5928 5929 // If a snapshot chainstate is in use, we want to find its next blocks 5930 // before the background chainstate to prioritize getting to network tip. 5931 FindNextBlocksToDownload(*peer, get_inflight_budget(), vToDownload, staller); 5932 if (m_chainman.BackgroundSyncInProgress() && !IsLimitedPeer(*peer)) { 5933 // If the background tip is not an ancestor of the snapshot block, 5934 // we need to start requesting blocks from their last common ancestor. 5935 const CBlockIndex *from_tip = LastCommonAncestor(m_chainman.GetBackgroundSyncTip(), m_chainman.GetSnapshotBaseBlock()); 5936 TryDownloadingHistoricalBlocks( 5937 *peer, 5938 get_inflight_budget(), 5939 vToDownload, from_tip, 5940 Assert(m_chainman.GetSnapshotBaseBlock())); 5941 } 5942 for (const CBlockIndex *pindex : vToDownload) { 5943 uint32_t nFetchFlags = GetFetchFlags(*peer); 5944 vGetData.emplace_back(MSG_BLOCK | nFetchFlags, pindex->GetBlockHash()); 5945 BlockRequested(pto->GetId(), *pindex); 5946 LogDebug(BCLog::NET, "Requesting block %s (%d) peer=%d\n", pindex->GetBlockHash().ToString(), 5947 pindex->nHeight, pto->GetId()); 5948 } 5949 if (state.vBlocksInFlight.empty() && staller != -1) { 5950 if (State(staller)->m_stalling_since == 0us) { 5951 State(staller)->m_stalling_since = current_time; 5952 LogDebug(BCLog::NET, "Stall started peer=%d\n", staller); 5953 } 5954 } 5955 } 5956 5957 // 5958 // Message: getdata (transactions) 5959 // 5960 { 5961 LOCK(m_tx_download_mutex); 5962 for (const GenTxid& gtxid : m_txdownloadman.GetRequestsToSend(pto->GetId(), current_time)) { 5963 vGetData.emplace_back(gtxid.IsWtxid() ? MSG_WTX : (MSG_TX | GetFetchFlags(*peer)), gtxid.GetHash()); 5964 if (vGetData.size() >= MAX_GETDATA_SZ) { 5965 MakeAndPushMessage(*pto, NetMsgType::GETDATA, vGetData); 5966 vGetData.clear(); 5967 } 5968 } 5969 } 5970 5971 if (!vGetData.empty()) 5972 MakeAndPushMessage(*pto, NetMsgType::GETDATA, vGetData); 5973 } // release cs_main 5974 MaybeSendFeefilter(*pto, *peer, current_time); 5975 return true; 5976 }